I'm all for constant relic bumps as long as some amount of effort is put toward upgrading it.

If they want people to do the content and still go for the new weapons... then how about they add a function where in order to upgrade your relic, you need to trade in these new high damage weapons. Some NPC can "fuse them together" to empower the RME. For those that don't have an RME, then you can still obtain and use the new weapon effectively like usual.