Lusche is right. The maps that have TT are barren most of the time. Why, I don't know, maybe it's because they are an easy place to carpet bomb a bunch of easy kills.
That ain't the reason either, as it doesn't keep players from spawning to places where they can bet on countless bombs raining down all the time. Again, Trinity TT is the place best shielded from enemy bombs that does exist on any map.
In short, two things did kill off TT as an institution: First we lost all big maps after the arena split, leaving only Ndisles with a TT. And this was neutered by a major terrain redisgn, pulling the spawns to far to the rear while at the same introducing a friggin hedge maze. So we had only one TT , which the players didn't use any more as before due to that horrible terrain at that time. And this simply broke the tradition.
When we got some big maps back about 3-4 years later (notably Trinity), a huge part of the community had never witnessed a fully functional TT environment in action, so they didn't have an idea what to do with it. And it's the same as with arena choice - nobody goes were nobody is.
Right now, I'm contemplating about starting one final try to get something going on Trinity again when the new KT shows up. Unfortunately I'm a bad organizer/leader and love in the wrong timezone. But it would be a shame to let this opportunity pass, whene everybody is eager to try the new tank but may be reluctant it up it at the usual spawncamps due to it's high perk cost. Trinity TT has many advantages, with everybody being able to drive home and land no matter what team he's on being a very big one...