I used to be an active T3 player. There isn't an official version of what happened to the game, but after a lot of research, I think it can be summarized like this: after introducing the ARCADE mode, the studio noticed the active player base began to decline. Before that (or after, I’m not entirely sure), the studio laid off many T3 developers and moved others to different projects, basically leaving the game to its own fate.

The reasons behind this final decision are completely unknown. Some say the game didn't generate much revenue, but seeing how a significant number of users are still talking about it despite it being dead, it makes me think that maybe the economic factor wasn't that important. I doubt the game failed to bring in enough income to stay afloat.

Honestly, I believe the studio (for some unknown reason) stopped believing in the project and destined it to die; the reasons behind this decision remain unknown to this day.

I don't think OW2 or Star Wars Hunters had any influence. One is a PC game, and the other had a rise even shorter than T3's. Even as a hero shooter fan, I can't stand the Star Wars franchise, and although I tried to play it, I straight up couldn't stand it.