Originally Posted by
Spider-Dan
This is usually true... though there are some exceptions, ST and 3S being the most notable ones.
MVC2, and to a lesser extent CVS2, occupy a weird space in that both of those games were the top-level competitive fighters for many years without an update or a successor. It seems like the tournament scene for both of those games is also largely burned-out, but it's a bit more understandable there given the length of time where those were the only games in town.
Basically, CVS2 killed both A3 and 3S when they were only a couple of years old, but only 3S managed to regain popularity. SF5 killed USF4; whether USF4 takes the memory-hole path of A3 or the resurrection path of 3S is still up for debate.