Hello, just an idea on how you could potentially increase the quality of the mentor/sprout system.
There is a TL;DR at the bottom.
I've seen a lot of mixed reviews in the system. Personally I tried joining at the start and didn't see much worth in the discussions happening in my server at the time, so I never went back as it was more or less just a social club with my questions getting ignored.
Before I get to into it. I'm the Lead Moderator for an official discord for another relatively well known game. I've been in this position for roughly 6 years, as leading communities is a hobby of mine. Currently my Discord server has 22k members, and includes a Mentor system I kick started. I have 1 Lead mentor, and 24 Mentors. That said, my process of choosing mentors requires a full blown interview. This is due to the community I run and the game itself. While not fully compatible here, there's enough overlap that my suggestions could be viable.
My suggestion is geared towards self moderation and overhauling the mentor system itself to become nothing more than the basic idea - a mentor is there to help the sprout, and nothing more.
To begin with, create a Private Discord for people who are Mentors. This discord will ONLY be for people with the mentor status in game. You can rely on the mentors themselves inviting people in via in game DM OR by sending anyone with the title an official Email from Square-Enix.
You'll need at least 1 Mentor to become the lead moderator. This moderator should be as unbiased as possible. The role of this lead moderator is to be a direct chain of correspondence with a FF14 CM to help moderate ALL mentor channels in the game. They'll be responsible for fielding reports from other mentors and moderators to give direct pertinent information to a CM to take quick action against other players utilizing the in game chat system for breaking the rules of the Mentor Channel (Trying to scam, not acting as a mentor should, starting arguments with other mentors, etc)
To find these players will require a FF14 Community Manager to scan the various mentor logs, and find several players across FF14 who are active in the mentor chat, typically send valuable advice to sprouts to begin with, and aren't prone to being emotional or arguing. This will create the basis of the Mentor Player Moderation team.
The Moderators should act as a player driven Quality Control of the Mentor Chat in their servers. The moderators (Not the Lead moderator) Should act as a report mechanism to the Lead moderator. They'll occasionally look at their own mentors chat and look for bad faith actors, or players not using the mentor system as intended.