I think that could be explained easily. I don't like worlds which turn around the "hero" and his/her group and I don't like companions which are 100% to the main heros taste and licking his/her ... all the time. As allegedly the world is big and wild, there could be space for more parties of heros traveling around. The companions you see in the camp during rests do their own business the day over, they are just too polite to inform you how boring your adventures are in comparison to their own.
Except in BG3, there is nothing more important to our companions than our current main quest: deal with the tadpoles. Except for maybe Gale's bomb, but he tells us about that and requires we bring him items, and therefore isn't going off on his own to deal with it. So it doesn't really make sense that the companions aren't putting 100% of their effort into solving the tadpole issue.
I think it'd be interesting if, when you don't make quick enough progress in reaching each companion's preferred method of solving the tadpole (e.g., going to the Gith Creche for Lae'zel), the companions become dissatisfied with you. First they have a talk with you imploring and then demanding that you go there next. If you continue to do other things, however, they leave you to go there on their own. You'd be able to find them again when you go there, but perhaps things have played out differently than if you had gone there earlier.
