Earlier quoted context omitted.
Book opening is fine. Post-it notes exist. You can easily open the book to the right spell. Just write down the names of the spells you have chosen to memorise for the day on a piece of paper and cross them off when you cast them. As for rules lawyering... That is just playing by the rules. That is how the game is meant to be played: rules as written except as modified by the group by agreement. Rules lawyering just…
It's a horrible experience. I can only suggest you try out TTRPGs that don't need this. I haven't tried it yet but Daggerheart seems to avoid the problem by providing spell cards. You can do the same in DnD and I suggest doing so, but it's not assumed by the game's design. All the old-school OSR inspired stuff doesn't have this problem. You should not need to repeatedly and consistently open the rule-book to play wha…
I used to make MTG style cards for spells, quest items, etc. something physical the players can keep with them.
This made casting extremely efficient as the caster has the card with the info on it. All they have to do is turn it in, roll the dice, and describe their action.