IMHO they are not mutually exclusive.
Sorry if my comments led you to believe I thought they were. Of course they can't be as many skills necessary for both apply equally. Hand hold, trigger control and, sight alignment are basic skills that can and should be honed to a higher level than most take the time to learn until it's subconsciously ingrained.
Learning to shoot under pressure, even self induced as it may be, is a learning experience and over time stress is less apt to affect outcomes/shooting scores. That puts the games squarely in the camp of increasing some ability to run the gun under some stress level until the competitor gets comfortable shooting thusly. Though the stress induced in the games isn't near the same, any system that produces some stress is more beneficial to shooting for self defense than never having had to shoot under any more stress than one isn't happy with not being able to drill one hole.
Now, as for scoring in the games, they suck at getting people to realize you don't NEED A hits or down Zero hits on the street. In fact, I think more will take too much time trying to acquire an A or down Zero hit on the street if they are heavier into the games for most of their shooting time.
Another point of difference I mentioned previously, I'd use 1/2 hip, 3/4 hip or zipper more often on the street and using only one hand, but in the games, I'd got to line of sight or near line of sight and two hands "for the score". If one were to zipper in the games, one would be wasting time for score, where on the street, the zipper is a fight winner and in the games it's a detriment to score.
Some of the tactics that win games can get you killed on the streets, like having to reload form cover when on the street, I'll reload as I'm moving to cover, no wasting time waiting to get to some position before I can recharge and get back in the fight.
I played the games for some time, mostly plate shoots which gave practice for QK pistol skills on multiples. IPSC and IDPA, not so much but enough to know I didn't want my present skills to be altered or degraded by the gamers rules.
There are no rules on the street and there's no "look see" beforehand, of the course of fire on the street. In the game of staying alive, there are no do over or procedurals. My biggest concern for gamers is that those procedurals they try to avoid for score could get someone killed unnecessarily
