Why should logged on time count in? I know tons of players that are way better players (and mentors) than me, and they only started playing the game half a year ago.
Why should they not be mentors despite the ability and willingness to be one, just because they didn't start playing back in 1.0 and have years of playtime logged? That seems like a really pointless requirement.
I'm also inclined to think that more mentors = better. Yeah sure, we get some bad eggs, but if you made the requirements crazy high, barely any mentors would be in the newbie chat at all.
As it is now, on the most populated EU server, we usually have 30-80 mentors online, and many are busy with their own stuff, so actively helping are..10-12 people?
Not the same 10-12, of course, as one mentor becomes busy another one starts having time to help, and so on.
Now imagine raising the bar to even become a mentor at all by a lot. We'd be left with maybe 10 mentors, of which 0-1 would actually have time to answer questions or run duties with the newbies. None or one person for over 200 newbies.
That seems like a horrible idea, sorry.
It's not like someone failing or being rude with a mentor crown means newbies will listen to him when they see him fail. The current requirements do so much good for very little bad (once in a while running into someone who brings shame to the title of mentor), I do not see any reason to change them.
And btw, the main job of mentors is to help players that are ACTUALLY NEW TO THE GAME. While I do think mentors should at least do okay in duties, what matters is how much they can help with the everyday problems newbies encounter, not how big their epeen on FFlogs for A12S is

If a player can't beat Zurvan EX or never entered Savage Alex, but can quickly answer where to get a chocobo, which classes are needed to upgrade to which job, what is included in the free trial, how to best level up in level range X, and knows very well how to do duties no one normally does that are required for story progression (like normal mode 4-man Garuda and stuff like that) I'd take them as a mentor any day over someone who's entire qualification is that he can beat A12S but is completely detached from the actual beginner's problems.
Phew. Rant over.