Everyone is new at some point, so they always get a chance. The ones who speak up quadruply so. If somebody says they are new in a dungeon, whether to that dungeon or the game in general, I'll gladly make conversation with them while attempting to set a manageable pace through the dungeon. It leads to a better experience for everyone that way.
On the flip side, I have limited patience for newbies who try and "sneak" into harder content like EX primals or certain Coils (looking at you T9). If they don't listen to any advice the party gives and continually cause issues, then they will be getting removed because I didn't sign up for a wipefest when I joined an orchestrion farm.