While I understand the desire to be kind and gentle to everyone, this is a game about murder where you get a majority of your experience from killing things. There are probably better games out there for you if this isn't the tone you are looking for. I'm not trying to be dismissive here, but honestly something like Undertale may be closer to the tone you are looking for. It has the option to both be a murderer and be extremely kind. If you haven't played it, give it a try. It's a modern classic.
Regarding the fallout comments, 1 and 2 definitely had some of the best dialog and impactful options of any game, with New Vegas right behind them. But 3 and 4 had maybe 5 consequential choices between the two of them.
Yes but most of the game is about "murdering" the bad guys.
Not sure if you mean BG3 or Undertale.
If you mean BG3, then yeah. Like most triple a games (that aren't sports related) the primary gameplay loop lots of murder. That being said, BG3 has more options to be kind and non-lethal than a majority of the triple a games market.
If you mean Undertale, then no, you can absolutely play pacifist beginning to end.