This becomes an even greater issue on servers. To the point of "Why even bother adding them into the game".
It will be hard enough getting enough for just a few players to have one, making them too expensive means after a month or so, they will no longer exist in game without cheating or mods.
I read that tweet as meaning renaming doesn't add to the repair cost, rather than renaming locking the repair cost to a fixed amount.
Until we know, keep open.