To reply to the thread title, I think criticism should always be allowed - the alternative is gagging.
However, I think everyone involved needs to count to 100 before posting.
I think the difficulty is that there are several different topics mixed together on the same forum, frequently in the same post, and it's difficult to separate them out:
1) Playing the game of MGT (which is equivalent to what happens on other parts of CotI). Unfortunately, this doesn't attract much attention from either 'party'. If it could be separated out, this is where MGT players should be able to discuss their version freely without interference. It has no bearing on how anyone else plays their version.
2) Errata, typos, and 'bad' calls in the published MGT material, supposedly bringing the game of Traveller into disrepute (doesn't vitriol do the same?) I believe the errata and typos have been addressed as far as practicable short of new editions, and 'bad calls' are necessarily subjective (some more so than others). Mongoose is even taking steps to address some of these with the aid of the critics who raised them. These are all good signs for the future of Traveller and the ability of the community to work together to improve the game we love.
3) The definition of 'Traveller'. This is the hottest issue and the least likely to be resolved to everyone's satisfaction. This is where MGT differs from every previous incarnation of Traveller. Some versions have taken huge liberties with the OTU history, but the basic assumptions of the game have never before been altered. This is the main reason why supporters of other versions come to this forum with concerns; because MGT isn't just a new version, Mongoose is affecting the very meaning of the term 'Traveller', and that affects everyone, not just MGT players. MGT players cannot expect that other Traveller players should not voice their opinions on this, but it would be good if this worthy discussion could be separated from discussion of MGT as a game (1 above). Attempts to do so by individual posters have failed so far.
Obviously Marc and Matt have discussed a future for Traveller, and it may not be to everyone's liking. It is unlikely that this community will radically alter those decisions, particularly not with outright opposition and hostility, so to that extent criticising their decisions is pointless. However, business plans are always evolving, and it may be possible to influence the decisions Marc and Matt make in the future by pointing out certain issues and making rational arguments (as Hans has done in supporting OTU canon) so equally it's not logical to argue for acceptance of 'the inevitable' on all counts.
As I see it, dealing with the OTU and 'Traveller as we have known it' is simply step one in Marc and Matt's vision (I could be wrong) and gradually it will receive less interference/support as Mongoose concentrates more and more on alternative settings such as Trek, Dredd and B5.
'Traveller' is expanding. Gradually, over time, the concepts of the OTU, current ATUs and 'Traveller as we have known it' will merge into one - the OTS (Original Traveller Setting) to coin a term - and this will be just one setting (albeit a favoured one) under the umbrella of 'Traveller - Science Fiction role-playing in the far future'.
At that point, some will get their wish (albeit not in the form they wanted) and everything they've called 'Traveller' for the past 30 years, all the Jump Drives, STL communications, etc, really will be rules and setting combined - only it will be a subset called the OTS, the Third Imperium or something else, and the name Traveller will belong to the wider ruleset umbrella encompassing B5 et al.
Like it or not, I think this much probably
is inevitable and no amount of complaining will alter it*, but we
can perhaps ensure that what Mongoose does with our own Pocket Universe of 'Traveller as we have known it' involves minimal disruption and clear signposting.
The way to do that is with continual but sensible petitioning at reasonable intervals - not a shut up about it forever, but not a daily kick in the shins either.
*It's about cash, and if Marc Miller chooses to alter some aspects of his imaginary game in order to improve his real life, I can't blame him. Wouldn't you do the same?