I'm not convinced that the gacha model works for every demographic. And even if it did, I'm sure it's much harder to be successful selling that kind of crap as an independent studio with no prior experience doing that. Maybe exploiting the D&D / Forgotten Realms franchise would have helped.. but after the OGL fiasco (which is a good example of how profit was affected negatively when D&D fans cancelled their D&D Beyond subscriptions on the wake of new plans for monetization by WOTC) I'm not really convinced the game would have made as much money as they can with this different focus.
Reputation also affects profits. And long term, I'm convinced Larian approach will prove to be more profitable than it would have been had they chosen to enter the wide and unforgiving world of competing RPG gacha games by introducing "yet another one" in a market that is increasingly tight, and with a public that is getting more and more tired of it.
Yeah, Diablo Immortal / 4 or probably even Fallout 76 made money with those tactics... but I don't believe those profits are gonna last that long, or reach an overall total as high as could have been when you think long term. They have managed to get a lot of people to stop caring about those franchises, so I'd argue they are actually burning down their golden goose just for a short big burst of cash, instead of actually maximizing the profit they could have made from the goose had they been taking care of it while steadily producing golden eggs people actually wanna buy...