BG3 has already sold more copies (over 2M+ just in Steam) in EA state than legendary BG2 in 20 years, P:K, and P:WotR combined. WotR, which GM4Him called successful, in comparison sold a meager 500k+ in Steam. So, your extreme point of view doesn't make sense.
In order to asses a game's success, you have to take into account the budget. Undertale sold 1-2 million copies and Cyberpunk 2077 sold ~15-20 million copies; but it'd be an extreme stretch to say that CP2077 is more successful than Undertale.
WotR sold 250k copies in its first week, so let's say ~1.5-2 million copies will be sold eventually (P:KM sold ~1 million after 3 years). BG3 sold ~1.2 million copies in its first two weeks of EA, so let's say ~15-25 million total? (For comparison, Witcher 3 sold 30-40M and DOSII sold ~500,000 after a week and probably 3-5 million in total - I found a source saying 2 million after a year) Roughly, BG3 will sell ~8-18x more copies than WotR.
P:WotR raised ~2 million on kickstarter, so let's say it cost ~$7-10 million to make (60 employees at $50k/yr for 2 years= $6M). BG3..."has a triple-A budget" so let's say $70-125 million. (250 employees at $50k for 4 years is $50M) Roughly, BG3 will cost 7-18x more than WotR.
