Tactful ways to inform people that they're playing badly?

[Hash_Browns]

At one point you needed Lancer at 30 and Marauder at 15 to unlock Dragoon.

Ok, I can see where this is coming from, but using a guide from like 2013 when a bunch of other guides from 2017-2019 really doesn't make sense, especially when you consider the fact that the official FFXIV job guide is the second result.