Yes, Overwatch is a great game, but imo it made the FPS genre (not just the FPS genre, but it especially) much worse. Let me explain:
Overwatch has loot boxes that can be bought with real money. Overwatch sold a lot, and because it has a lot of fans that think it's a sacred game and refuse to consider the loot boxes a problem, publishers now think loot boxes are a-ok with consumers.
Overwatch has no campaign. Overwatch sold a lot, and because it had a lot of fans that think it's a sacred game and refuse to consider the lack of campaign a problem, publishers now think it's a-ok to don't include a campaign in a $60 game if it has a multiplayer mode. That's a more recent one, but with CoD BO4 not having a campaign, we can expect the number of FPSs with single-player content shrinking more and more from now on.
Overwatch also won tons of awards, including Game of the Year (!) on TGA 2016.
Overwatch basically made anti-consumer practices acceptable in the eyes of publishers.