There is no such thing as "best" game or studio, it's all very subjective. It's like making a list of most beautiful movie actor or actress of all time: usually all just commercial lies. When it's about what made the deepest marks on you, the commercial success or the oppinion of the majority means nothing.
Of course our subjective opinion isn't better either, so no point arguing ever: all we can say, what we liked and maybe why, if we still remember it.

Bioware isn't the same or ever was in the past: they evolved, changed, improved and also faded away; may return with quality or not. Not the same people, it's mostly a name, though a name which inspires and creates high expectations for a good reason.

Baldur's Gate 1 & 2 are very much overrated by some (and that's okay), because there wasn't anything better back then. First love is greatest. They aren't bad, but just finished BG 1 and playing BG2 now, and nothing to make me cry in there. Aged games, so won't bash them either.

Skyrim was horrible without mods (I quit after 1hr or so), but mods made it an amazing place where one could do nothing just listen to the sounds of nature & weather, and relax for hours. Forest and rivers, if one had a PC to run it on highest of course. Great background music as well. Not much gameplay, but the main story was decent and was fun exploring every corner a few times.

Witcher series are a special kind, very different atmosphere. Avoiding the fighting with mods (don't afraid to mod out annoying parts), the story and the world were captivating, with emotional moments along.

Obsidian creations is among the best, though one have to pick the good parts and ignore the rest, same as with any other game. The emotions in the voice of Grieving Mother (voice actress Tara Platt) alone made Pillars of Eternity a game that can write it's marks deep. Many great voice acting in that game, and though it's a sad story, the game is thought provoking and can teach more about life and choices, than usually 4 years of school does.

tl;dr -- never follow my recommendations or reviews, or those of anyone: see for yourself, you need to taste it, feel it, because you may miss out really amazing moments if you just follow others; what marks you is unique to you