Everyone can talk in one conversation? Offering their rolls to conversational choices? Why have choices at all then? You are loading the dice. How is this even fun when you "win" every conversation? Why. Roll. The. Dice. At. All.
There is a difference in failing a check when a character tried something they are decent on, then failing with something they can't do at all. No I don't want my rogue reading this arcane book and failing because guess what, i know he will, i want the wizard 2 feet back to try instead. Now if he fails, sure, w/e, lets move on! D&D is a team game. Not a single person game. The team works together to overcome challenges, not look around at butterflies while one character does everything, ESPECIALLY when you get ambushed into a convo and the person they talk with is...less then ideal. This isn't a solo adventure, it's a team of adventurers.
Every crpg does this now. Pillars, Pathfinder, Wasteland, even Solasta with its much smaller budget and team, because they realize that you're playing a team game. As a group of adventurers.
I'll grant you the ambush conversations, you should probably get like an initial decision point of 'Who would you like to talk?" type of deal, but outside of that, no, sorry. Someone failing at something they can't do at all is them failing because they NOT SUPPOSED TO BE GOOD AT EVERYTHING. Your book example they already solved, when its an item or an area check, everyone gets a roll. But when you have a conversation with another person, you dont listen to each sentence, and then turn around to your group of friends saying "HEY WHAT SHOULD I SAY HERE? DOES SOMEONE ELSE WANT TO INTERJECT?" Thats not a conversation. Thats loading the dice. And if you DO do that, the person, creature, whatever, would ABSOLUTELY have a reaction to that situation, and would just say "ya I know what you are gonna do now and now you lose instantly." or something to the degree of making the roll EXTREMELY hard, even if you are proficient at the check, because you literally just announced to the room that you are changing it up for the sole purpose of 'winning' (for lack of a better word) the conversation. I realize when you play a tabletop game, with a DM, you all are CAPABLE of talking out of character, and making that decision as such. But this is you playing a character who is alive and truly acting things out as they come. The situation you are wanting does not have a place here. It just doesn't make sense, other than loading the dice in your favor.
So when you and your friends are out as a group and you all bump into another friend or a sibling, does your entire group stand behind one person refusing to give input so that the conversation only involves you and the new arrived individual? The reason other games do this now is because it more closely emulates how social interaction actually works. People dont stand silently behind one elected speaker and not offer input or their expertise on a topic.
If you're out with your engineer brother and you get asked a random question about engineering don't you think its possible or even likely that your brother would chime in? You're interpretation is absolutely silly. Of course your party members would chime in, I don't think its appropriate for all rolls but there are many where it would be silly and inappropriate for your party members to stay silent or not intervene.
Edit: A good example of what i mean would be Gorion's Ward about to touch a dangerous looking magic rune while Edwin is standing behind them. If Edwin likes him, it's a chance for Edwin to demonstrate his superiority by saving him, or it might be a potential opportunity for Edwin to remove Gorion's Ward from equation by pretending not to be watching. Party members contributing to or even taking over rolls is an excellent way to build upon your companions' characterisation and improve immersion.