Let's Get Real - the DM's responsibility is balance

[ad_hoc]

I would far rather prefer for the dwarf barbarian to be engaged - if not necessarily to the party's benefit - in negotiation with the Elven King than than have the player "check out" because "this isn't their thing."

To pick this one part out in particular.

When I DM every character who is present in a social encounter makes the Charisma check if one is called for.

They all get a chance to participate by saying something. If they don't say anything they get disadvantage to their roll. It doesn't matter how Charismatic the Bard is, if the rest of the party 'checks out' the king won't be impressed.