That is what a well run early access program provides, and it paid off with Larian and BG3.
But do you agree that this is the exception to the rule, many early access games fail to deliver what they promised, no matter the good intentions.
The "No DLC" thing is mostly just a Larian preference and not specific to BG3. They've never been big on it.
But the funny thing is, there is Larian DLC:
Baldur's Gate 3 - Digital Deluxe Edition DLC
Divinity: Original Sin 2 - Companion: Sir Lora the Squirrel
Divinity: Original Sin 2 - Divine Ascension
Divinity: Dragon Commander - DLC: Imperial Edition - Upgrade
Their early games (Divine Divinity, Beyond Divinity, and Divinity II) all predate online stores that allowed for DLC, the games with DLC are all after 2010. Divinity II had an expansion pack called "Divinity II: Flames of Vengeance", that you would buy physically (proto DLC)...
Sure, these are not DLC schemes like EA, Activision, Paradox, etc. But there is DLC.
I think BG3's success is directly related to the quality of the game itself. There have been plenty of games that were hyped and ended up falling flat on its face upon release because nobody liked it. Sometimes a decent game doesn't find an audience, but I can't recall a bad game becoming immensely popular.
Looks at EA and Activision games... You were saying...

There are TONs of games that have hyped immensely, have become immensely popular, have made tons of money and are deeply flawed. It also depends on what you mean by 'quality', do you mean technical 'quality', like in literature? Or something else? Because the issue with technical 'quality', is that many people might have read Shakespeare, but I wouldn't call it a fun, entertaining experience. On the other hand there are tons of people that are having cheap fun with pulp novels and dime store romance novels. CoD is immensely popular, every time, but I wouldn't call it 'quality'. Big Brother reality TV I wouldn't call 'quality', but it's aired 508 seasons in 63 countries/regions...
What I mean by hype and gaining traction outside the normal niche. I've seen/heard people
buying BG3, while they normally wouldn't touch a cRPG with a ten-foot pole. I wonder how far those people actually played before moving on to the next shiny.
I'm not saying that BG3 is a bad game, I'm saying that we should separate the hype from the actual game. 'Platinum' status, thus sales don't say anything about quality, it just says something about sales. And while the owners of the IP and the developer do rank how 'good' a game is for them, based on sale figures, that's because they look at the game from the money perspective. They are a business, they work for money. We are consumers, the only thing that should factor money in, is if it's 'worth it' for the money, and that determination is different for everyone.