One thing people seem to forget about barebones CT. Combat back then was applied to the Strength, Endurance and Dexterity Attributes. However the first time you took damage in that fight all the damage was applied to one of those stats determined at random. (Which generally exceeded that single stat.) Reducing one stat to 0 rendered you unconscious and out of the fight. So in that way CT was more deadly than T20. However Snapshot, Striker and later incarnations of Traveller changed that nasty feature rendering later incarnations less deadly. T20 is deadly in a reasonable way though mid to higher level characters can slug each other all day long with no appreciable effect. (So as long as we are doing non-lethal things nobody really gets hurt. A Brawl, as long as nobody pulls a lethal weapon can go on for days. (Kind of makes the fight in "The Quiet Man" look like a short fight.)
Now one of the things to reduce the level of violence in your campaign, and limit the big bad characters with lots of loose cred from shooting up your entire campaign because they have all sorts of armor to absorb damage, is to have law level also apply to body armor. At mid law levels anything more than light armor would be frowned upon. And at any law level where military weapons are outlawed Combat Environment Suits and better are also illegal. (Of course that doesn't prevent the Military or local Law Enforcement from carrying military grade weapons so they may also have Military grade armor.) Further someone toting mil-spec weapons and/or wearing milspec armor doesn't get to run into the local beat cop, they get the SWAT team.
If things really get out of hand, IMTU, the Marines, or even threatening to send in the Marines generally quiets things down. Gunning down local police and fleeing through Jump-Space is one of those crimes that, IMTU anyway, gets the MOJ involved. While the MOJ, IMTU isn't the Imperial Marines, they might be accompanied by a Squad, if necessary.
I said all that to say this, if you remove MilSpec Armor from the equation, then T20 is just as deadly, when it comes to lethal force as CT. However unlike CT you can actually brawl all day long and both sides walk away.