+1 JECE. PPSC and WTA lead to thoroughly different endgames (assuming players are playing rationally for points outcome, haha look at my spherical cow).
I don't actually think the difference matters *that* much to early or mid game, where you're really still trying to set up to survive and maximise your opportunities to solo and stay in the draw.
But, the key difference is once you hit the point where a player has a clear run at a solo opportunity.
In PPSC, it is usually in your interests if you're not that player, to simply switch to protecting your SCs and trying to grab any more than you can, giving up any interest in draws, solos, or anything else.
In WTA, you need to start thinking about uniting opposition to the solo threat, and since there's no difference between survive points and lost-to-solo points (both zero), you might as well die trying to make a stalemate line than to do nothing.
(Obviously to return to the spherical cow, there are *lots* of reasons why those aren't the only things people might validly want to do during endgame, starting with that some don't give a crap about points or ratings whatsoever, but I'd say that's the main big difference between the two when players are playing for points.)