Keep in mind, Solasta and BG 3 have different target audiences. What is fun for one audience may not be fun for the other. Both games are in EA, but let us for a moment consider the size and scope of the 2 markets. Here are some numbers from steamspy (keeping in mind that steamspy's numbers are not 100% accurate, but we can still be somewhat confident in them).
Its blatantly obvious that the crowd of people buying the one game, is not the same as the crowd of people buying the other.
Mmmm. I attribute the high numbers to a) the Baldur's Gate name b) the D&D label c) Larian's reputation. In that order.
Tactical Adventures is unknown company making a low budget, combat-oriented, SRD game with next to zero hype around it. What's kind of amazing that is that producing such a good game with all the marks against it. Were they to get the Baldurs Gate 4 contract I think the numbers would be comparable.
Don't get me wrong -- BG3 is better in some respects like story and roleplay but Solasta excels in term combat. Best fight in BG3 is the hag fight because it's creative (illusions, alignment-related dialogues, advances a quest) *and* because it doesn't take any homebrew rules to win. No barrels, king of the hill, surfaces or dipping required to finish this one. That quest makes the game imo.
Compare that to the mud mephit fight which is another surface / king of the hill fight. The ancient tree quest feels like a toned down version of DOS2 battle. Not as good as DOS2 and not D&D either.