Nope it's not an issue! At least not in my opinion.
It's what make these games so great!
NPCs are not mules carrying your loads, or stupid being having no other reason to be but being cannon fodder and stepping on every darn traps killing you in the process.
NPCs have a personality, they are fun to listen to, they banter with each other, talk, have things to say and share, I actually spent like a third of the game listening and talking with them. You end up caring for a character you might not have liked at the beginning, you think of which one to take with you taking in consideration which talents he or she will bring to the party but also how they might react to the situation and how the'd interact with each other!
You can care for them since they're not bi-dimensional!
And yes, they can leave you or betray you, or confront and fight you if you choose a path they do not care for, or you offend their way of life and thinking, they also can like and love you.
As for alistair he's a bastard whom had been raised with a mixture of love and neglect in a castle and a monastery, he cannot leave, since he's part of the story and you can befriend him and help him to grow as a person...
And there's choices, you have to decide whom you side with, and face your choices unlike the elder scroll where you can be head assassin and human kind savior at the same time, kill and rob people without seeing any consequences...
I loved these games! Did not care much for the elder scrolls for all above reasons. So tastes, and inclinations and all of that...
Did not play baldur3 so don't know.