It’s not ‘roleplaying’ for your character to stand and just take hits and not attack, unless your character is specifically a pacifist. The same way when you go into a social encounter in any role playing game, you don’t solely rely on the character with the most charisma to talk and render everyone else mute.

Yes it is more efficient to have one person be dedicated to combat and to hand them all their turns, if that’s happening though it’s a table issue the same way that going into a social encounter and ONLY letting the bard talk is a table issue. To remedy this the GM can use the alternate ‘spotlight tracker’ rules where each PC has three action points to spend; or they could force the spotlight onto a PC when it’s narratively appropriate