Methinks you're a Blizzard fanboy.Diablo 3 was a critical and personal dissapointment. Starcraft 2 and Heroes of the Storm aren't exactly in my list of top PC games either. And they make more money?
I haven't seen exact figures, but you are severly underestimating how much cheddar people drop on stuff like Team Fortress 2 items.
As for the diversity in types of games, you're suffering from recency bias. Until basically a couple of years ago, Blizzard only made point and click type games/RTS-like controls (Star/Warcraft, Diablo). WoW had the same feel as W3, just with a different camera position and WASD movement. Portal (a unique puzzler), Left 4 Dead(unqiue co-op, multiplayer experience, progenitor to Destiny), DotA2(an entirely new genre/RTS evo), and Half-Life(FPS) are at least as diverse as Overwatch(FPS), HotS (yawn, bad design philosophy to leveling up as a team. just like some of us are 10x devs, some are 10x MOBA players), Hearthstone(card game), and WoW.
Their quality control is excellent, I will concur. They rank up there with Nintendo for having extremely polished games with few if any bugs...none gamebreaking that I remember. But the reality is a tightly controlled xperience is just less satisfying and has far less replayability.
The crowd is just going to make a better game, period, because they can suit a variety of gamer's preferences. I barely scratched the surface of any campaign in Starcraft 2, didn't like vanilla multiplayer, but played the shit out of the modded custom games.
Look at a game like CounterStrike. I remember getting into that game 18 years ago!!! and it's still one of the most popular esports, twitch channels, is even on cable TV, and still makes boatloads of money.
I really don't care much for PvP FPS experiences, which is why Overwatch, while a fantastic game that actually gets me to play PvP, is unsatisfying. I much prefer co-op games and I really liked the horde mode, but they make it seasonal...so I haven't touched it in months.
What's really infuriating is that I enjoy modding and creating new game modes and OVerwatch's game/gunplay is so sublime that I have tons of ideas. One of the low hanging fruits is adding a MOBA mode with creeps, stat-based leveling and items. Another one is creating maps with more open spaces. or a co-op puzzle mode where you must use certain team configs to solve challenges. There's so many possibilities and with the core engine being so buttery smooth, I see no reason why modders couldn't make the game relevant for 10+ years
Again, I am mystified as to their strategy. Did they resent the creation of DotA, say to themselves never again, and decide to completely abstain in creating modder tools? I'm being hyperbolic a bit...they're entering uncharted territory by making a competitive FPS and want to tread carefully. As I researched, I read they are soon releasing modding tools. Looks like I might be playing overwatch again soon!