I won't mind explaining mechanics if they're simple, but some fights have so much going on that text would probably cause more confusion than help, not to mention how much of a waste of time writing and reading walls of text would be. You also need people who are actually able and willing to learn mechanics and don't just wanna faceroll through the extreme fights out of ignorance. There are also instances where even after you explain stuff, people don't follow the instructions for some reason. And if you get thrown into a party where the other members don't speak the language(s) you do, welp, you're out of luck.
People easily throw around "That's your job as a mentor!" "If you don't want to help, don't become a mentor!" "Earn that mount!" etc., but they don't stop for a second to consider things from other (valid) perspectives. (This last part isn't directed at you, by the way XD)