CT as written is "each non-weapon skill is a custom rule"... some treat those like AWE/PBTA moves; others as starting points to mechanicalize further...
Most CT players I played with played '81... which hardly changes the variety of unique skill rules... and Books 4-8 add more. So does Sup 4.
My preferred edition, however, is a somewhat hacked MegaTraveller (needed rolls up 1 point, atts as assets changed from att/5 to att/3, use vehicle mechanics and large scale combat mechanics with mayday movement, alter the Pen:AV thresholds).
But, to be snarky, it's likely replaced by Alien.
ROFL! Back when I was really actively running Traveller all the time I pretty much ignored all the 'skill specific' rules, unless they happened to embody a particularly significant sub-system within them. We played strictly an 8+ success with standard factors sort of game, no varying that number, etc. While we didn't codify our approach in any way, at least at my table, any check had to lead to story significant outcomes. So if you went to certain venues and looked for a specific sort of patron, you would be checking Streetwise, and SOMETHING would always happen. There was no such thing in our games as an 'empty result'. If you didn't hit 8+, well you found something, it just wasn't a guy that was going to pay you money to do a job!
I found the skill rules to be useful in terms of helping to define and differentiate the various skills from each other. While Traveller didn't tend to pile HUGE numbers of skills into the game, like BRP-based games for instance, there could be times where you asked "is this carousing or streetwise?" The books would generally clarify where a given course of action was intended to fall, though not always.
Of course the combat rules are a bit of their own thing in this regard, as they provide some more complex interactions between various factors, and form a larger cohesive system. I'm pretty sure we always played those straight up in accordance with the '77 rules, although in most situations we may have 'fudged' certain things a bit.
This is why I say that something like a PbtA framework would slide right into place with Traveller. While our understanding of 'narrative play' wasn't very sophisticated, I think it does come close to what was intended by Marc. Basically when you make a check, you state a GOAL, and the outcome of the role is adjudicating that, not necessarily the detail of "did I crash?" but maybe more "are we in a fictional situation to continue the chase?"