I'm not a sprout anymore but I always inform the party when I do an instance for the first time. Maybe I'm lucky, but I never got verbal backlash. On the contrary I find that it makes people more indulgent and even sometimes make them chat a bit.
The funny thing is that sometimes just saying "I'm new to this" and "sorry" if you happen to play badly even brings you recs.
I will always be indulgent to someone who says they're new or simply not a very good player. And I don't expect newbies to watch or read guides before every new dungeon or normal raid.
Anyway, I'm glad you got to meet those "good apples" at last![]()