The only "You don't have to spend money"-games are like Dota2. In Dota2 you literally can't get any gameplay advantage by spending money. You get different visual effects or audio effects and that's all.
All the other freemium models are just tricking you into thinking you don't have to spend money.
And even that is still quite gambling-like, if you think about it.
I was plating DotA 2 recently. And while I didn't care for skins I was shocked that I was catching myself expending a lot of time exploring skins and managing inventory and the game rewards system. What was supposed to be a joyful and challenging activity became an excuse to addict and milk players.
The game is definitely fun enough on its own. But it went from "a fun game that gave me coins via lootbox duplicates that I could save up for some great dance emotes" to "a fun game that no longer has free cosmetics or dances, and therefore is now a fun game that is less fun that it used to be."
Plus I paid $20 or whatever for OW1. That game no longer exists. I would have happily paid $20 for OW2, even $50-60. But since I don't subscribe to the pay for cosmetics model, now blizz gets $0 from me, and I just accept I won't get cool new dances.
A lot of the time, even if the game /is/ rewarding enough on its own, the game you're really playing is still "lootboxes". Las Vegas casinos have roller coasters, live music, theatre, quality restaurants and various other attractions inside them. Some of them would even be worthwhile attractions on their own, but they're ultimately still adverts for the casinos. Gambling is just so profitable that they can afford to make their advertisements entire other fully-functionig businesses.
The market seemed to agree that OW1 was a good game. It had a good player count and looked like it made decent money. Until the end of 2019, when Activision/Blizzard decided to basically halt all work on OW1 in favor of work on OW2. It didn't help that Blizzard also moved all esports content (which they consolidated under their hat) from Twitch to Youtube at about the same time.
Which is the main reason I stopped playing. I can understand why they were removed but the lootboxes in OW1 could be farmed at a quite reasonable pace and beside cosmetics they also dropped a currency used to unlock specific items. Meanwhile I don't even know what that battle pass in Overwatch 2 does, the only thing Blizzard's marketing managed to tell me is that they want my money.
All the other freemium models are just tricking you into thinking you don't have to spend money.
And even that is still quite gambling-like, if you think about it.