QoL feature for better remembering players that went by a different name.

[Rongway]

If they want you to know their old name, they'll tell you what it was themself.

There are lots of reasons someone might change their name, and many of these reasons include some desire for anonymity.

[Jargal]

If they want you to know their old name, they'll tell you what it was themself.

There are lots of reasons someone might change their name, and many of these reasons include some desire for anonymity.

I want a feature for a video game, and don't care for this 5th grade behaviour nonsense. Either that or then a feature to auto remove me from their friendlist (and they being removed from mine) automatically.

I have people worth of years of playing the game. The suspicious behaviour aside (if someone from my friendlist is changing their names way too often), if they have a desire to distance themselves from the people they used to know, then by all means, at least a feature to solve the issue of my friend list having new names out of nowhere.

[Rongway]

friend list having new names out of nowhere.

Just ask them who they are. If they don't answer in a reasonable amount of time, maybe they don't need to be on your friend list.

[TabrisOmbrelame]

There are lots of reasons someone might change their name, and many of these reasons include some desire for anonymity.

Sadly, some of those people are stuck inside Friendship list of other people, which allow those stalker to still know who you are by some simple deduction.

A feature to remove our name from other people's friendlist is something that is often brought to the table by many players.

[Nezerius]

If they want you to know their old name, they'll tell you what it was themself.

There are lots of reasons someone might change their name, and many of these reasons include some desire for anonymity.

Going to assume the #1 reason of the ones you're referring to is stalking, a simple namechange isn't really going to avoid that. Anyone who gets to the point of stalking will likely rely on a player's lodestone id, which always remains the same.
I don't think this reason is enough to not implement a feature that the OP is asking for, especially since they could just make it a feature that players could opt out of if they wish to.

A feature to remove our name from other people's friendlist is something that is often brought to the table by many players.

Yoshi-P mentioned about a friendlist overhaul, that'll include this exact feature, during a Korean live letter back in January. Although I don't think anything's been mentioned about it ever since.