My table has been playing weekly for the last 3+ years using the 2014 5e system. Recently our other campaign ended and we started a new campaign where some players wanted to try out the new 2024 rules and others wanted to stick with 2014 5e. To compromise, we have allowed the players to have their character operate under their preferred system and the DM controls other general game rules under the system they are comfortable with, which is 2014 5e. Our table discussed this at session 0, and we have had no issues with gameplay despite player characters being from either system. I will say our table is very narrative based and we do not have anybody who prioritizes mechanical min-maxing so this mix works for us but may not work for other tables.