It's an interesting issue - I think Mongoose has been pretty straightforward as to their plans - they certainly see Traveller as a ruleset for multiple settings, many of which are quite compatable with the traveller universe.
So, does that make it generic ? Probably not. there's a lot that the rules don't do well in that regard; and frankly, I'm not sure the hobby needs another "everything can be plugged and played SF ruleset" - on the one hand there are some very successful examples (Hero, GURPS), but tons of failures (not listed in the interest of diplomacy..

Plus, I still like some of them).
I think perhaps the best way to look at what the rules are is that they are a very good toolkit for creating campaigns that are of the "traveller genre". Which is circular, but bear with me.
I'm going to suggest that despite Aramis' correct observation that the universe predates the rules, that the universe certainly began driving the rules almost from day one, and has essentially defined the traveller genre of stories and universes, much as D&D has defined its own genre of Fantasy. Both can link to a large but far from inclusive body of fiction (swords and sorcery, middle earth, comic book conan for D&D) but really define their own set of genre conventions whithin which they work very well. So, Traveller as a rules kit is driven by the imperium in much the same way (and for the same reasons) that D&D is driven by the original campaigns of its founders -Greyhawk & Blackmoor).
Does Traveller do the ITU well ? Yes. Foundation series ? Yes, Poul Anderson classic empires and traders ? Yes. Transhumanist and cyberpunk ? No, not at all. I honestly don;t think it'll ever be successful as a truly generic set, nor do I think it would be worth trying.
D&D is much the same, and love it or hate it, it really has found its own niche and market, and defined its own genre. In many ways, given how early in its field traveller was developed, it isn't surprising that it developed similarly - if not as all-encompassingly.
So, to the point of the thread. I think MG has realized this, and is supporting the traveller
genre, and doing it quite well. b5 and Strontium dog are excellent choices that fall well within the Traveller Genre of stories. Are they going to support the ITU ? Yes, as one of the genre; probably more than the others, due to market potential, but certainly less than a pure Traveller house, simply to dispersing the effort across several universes, as it were. Besides, a pure traveller approach would put them in the unplesant position of constantly competing with all the other traveller material ever produced, and editing issues aside, MG does not seem interested in either retreading or trashing the older stuff, and more power to them.