Yes, but not to the relative power within the Imperial forces. That's the problem. The Imperial Navy doesn't exist in a vacuum (so to speak

). Have a look at these roughly equivalent navy and army formations and the ranks that command them:
Navy...............................................................................Army
Ship (Navy captain (O6)).....................................................Regiment (colonel (O6))
Division <2 ships> (?)[*]......................................................Brigade <2 regiments> (brigadier (O7))
Half-squadron <4 ships> (?)[*].............................................Division <2 brigades> (major general (O8))
Squadron <8 ships> (Commodore (O7?)).................................Army corps <2-3 divisions> (lt. general (O9))
System fleet <2-3 squadrons>.............................................Army <2-3 corps> (General (O10)
Numbered fleet <8-10 squadrons> Fleet Admiral (O8?!)..............No equivalent
Named fleet <2-16 numbered fleets> Sector Admiral (O9?!!))......No equivalent
Entire Navy <~22 named fleets> (Grand admiral (O10?!!!)).........No equivalent
I repeat: An admiral commanding a fleet that covers an entire subsector is NOT the equivalent of a major general, but someone much higher up the chain of command.
Hans
[*] EDIT: To head off a digression: I'm not suggesting that divisions and half-squadrons would be distinct command levels the way brigades and divisions are; I'm showing why a squadron is the equivalent of an army corps. At least, a squadron of battleships is.
Ok, there are a couple of issues with this line of argument. First, I would say your chart seems to be a little off. It should be based on a "maneuver element" of some sort so we can establish a base line for comparison. The problem is, even at this basic level, you start running into problems with comparisons. On the Army side it should be the battalion, which is an O5 command, but on the Navy side, if we use capital ships as the maneuver elements, we are at an O6 command already from the start. But, it is what it is, we are dealing with very different tactical structures and we have to accept that.
So, let’s go to the chart, but rework it for tactical responsibility:
Navy....................................................................Army
Ship (1 capital ship (O6))...........................................Regiment-Brigade (3-5 MEs (O6))
Division (2 ships (Senior Captain Present)).....................Independent Brigade (3-5 MEs (O6/O7))
Half-squadron (4 ships (Senior Captain Present))............Independent Brigade (3-5 MEs (O6/O7))
Squadron (4-9 ships (Commodore (O7)))……...................Independent Brigade (3-5 MEs (O6/O7))
Task Force (8-27 ships (Senior Commodore (O7)))…........Division (9-25 MEs (O8))
Numbered fleet (64-270 ships (Fleet Admiral (O8))).........Army Corps (18-75 MEs (O9))
Named fleet (128-3500+ ships (Sector Admiral (O9)))......Army (36-375 MEs) (O10)
Entire Navy (~22 named fleets (Grand admiral (O10))......................No equivalent
Rank systems are designed to service the command requirements of a military force. The re-worked chart works to show how you can do that with the system as is. A squadron is actually more on par with an Independent Brigade rather than an Army Corps. There is a slight disparity between the services, but not a huge one where responsibility is concerned. But it seems perfectly reasonable to me given the command level requirements.
This is also consistent with CT character generation, which provided for a much easier commission and promotion probability in the Army over the Navy, thus implying that, in CT at least, if you wanted rank, you joined the Army (5+ without any bonus). If you wanted space skills, you joined the Navy and accepted your chances of getting a commission were small (9+ even with a bonus for high Soc). Book 4 changed that, but MT basic CG is the same as CT. That implies that everyone in the Traveller universe would know it is much easier to get a commission and get promoted in the Army thus making Army ranks “cheaper” by comparison. Being a Navy Ensign means a lot more than being an Army Lieutenant in the Traveller universe. Therefore, I would argue, being a Navy Admiral of any rank means a lot more than being an Army General of any rank in the Traveller universe.
You seemed to be totally focused on the disparity of a “local” Army commander having such a higher rank than their Navy counterpart due to the grater firepower and tactical responsibility of the Navy commander, but there are lots of examples of this thing in the real world today where it causes no problem.
Let’s just take a look at the modern US Army. Company command is an O3 position.
A tank company has 14 M1s each armed with a 120mm cannon, a .50 caliber heavy machine gun, and 2 x 7.62 general purpose machine guns. By itself it can cover a 4 kilometer section of the battlefield.
A Bradley Infantry Fighting Vehicle (BIFV) company has 14 BIFVs each with a 25mm chain gun, a TOW II missile launcher, and a 7.62 general purpose machine gun plus over 60 dismounted infantry with 9 more general purpose machine guns or 9 Javelin missile systems. It has the same battlefield coverage as an M1 company.
A light infantry company has roughly 100 infantry small arms, 6 general purpose machine guns, 3 Javelin missile systems, and 2 light mortars. By itself it can cover roughly 900 meters.
So, should an M1 company be an O5 command and a BIFV company an O4 command, rather than an O3 command because they have so much more fire power and can cover so much more of the battlefield than a light infantry company? You could probably make that argument logically, but it doesn’t work that way in the real world.
Going farther with this, a light infantry battalion is an O5 command. It has 3 light infantry companies, 4 TOW II missiles, and a medium mortar platoon. It can cover roughly 3 kilometers of battlefield. But if an M1 company is attached to support a light infantry battalion, the M1 company commander is under the command of the light infantry battalion commander, even though the M1 company arguably has more combat power and can cover more of the battlefield itself than the entire light infantry battalion. Nobody has any problem with this arrangement. And this is within the same service. It doesn’t take into account the variance of tactical and operational conditions between the Army and the Navy.
Ultimately, the Army and the Navy have different officer structures because they are built in very different ways. The Army is a labor intensive service. You take manpower, and you equip it in a way to accomplish a specific set of missions. The Navy is a capital intensive service. You design ships to do specific sets of missions, then you find people to crew them. The command requirements for those two types of forces are very different, and produce different rank structures to deal with them.
Just my thoughts.