It's not a problem that we are the leader of the group, it's a problem because it doesn't make sense why all the companions blindly follow you. Take DA:Origins:
-Alistair: His personality is that of a follower and he fought with you at Ostagar. Makes sense he'd follow you.
-Dog: Is a dog. But more specifically, you had to save him to get him as a companion
-Morrigan: Her mother tells her to travel with you and help you. As she is an apostate, she can't be the leader of the group and recruit allies.
-Lelianna: She sees a vision from the Maker telling her to aid you
-Sten: You literally rescue him from a cage
-Oghren: Joins you temporarily to find his wife. After you deal with Branka, showing your worth and the valid threat of darkspawn, he joins and recognizes you as a leader.
-Wynne: Again, joins you temporarily to protect the circle. After you prove your worth, she joins you.
Every companion in DAO has their own personality and presence, but also has a good reason for following you. They are told to help you, you prove your worth to them, or they are just unquestionably loyal people/animals. Now take BG3:
-Astarion: Boils down to: "Eh I suppose it's better to work together." Note, "work together." Why couldn't he be the leader and you the follower?
-Shadowheart: Same thing, "it's better to work together". Why aren't we equal partners?
-Lae'zel: Makes the least sense. You fought with her on the ship, sure, but she is a dominant personality. In reality, she would take over or leave. Or you could intimidate her into submission
-Gale: Makes the most sense. He's a happy-go-lucky guy who is fine not being in command, like Alistair
-Wyll: Also makes sense. You save the grove and he follows you because of that, and to have help finding Spike and killing the goblin leaders. After you deal with Spike/Goblins, you have proven your worth to him.
In total, only 2 our of 5 companions in BG3 have reason for you to be the leader (2.5 if you argue that attempting to save Shadowheart makes her want to follow you). However, this is an easy fix! Just add dialogue where companions voice their grievances and/or vie for party lead, and you can attempt to convince them of your leadership skills. These dialogues could happen face-to-face, or as interjections while you talk to NPCs. If they get too unhappy, they might strike off on their own (and you could find them later??). Then, once you've proven your worth (defeating the goblins/getting a big lead on tadpoles) or otherwise made your companions sufficiently happy with your lead, they have a cutscene/dialogue where they commit to follow you.
Well, my character did have to explain to Lae'zel that she was not a subordinate but a partner and that Lae'zel should show some respect.
This is a good example of companion dialogue that should happen with everyone