I'm against limiting things like respec and unsockets so that it's impossible to do at some point. But all for making it HARDER. Eg a more complicated recipe to make respec potion. So that respec potions can perhaps even have trade value.
I'm very against things like cotw being impossible to unsocket. Instead just make the unsocket recipe expensive, as expensive as you like. Just not impossible.
Long ago one of the selling points of the mod was the fact you had the freedom to unsocket stuff. I get that stuff like the 6 lab runes in armor should not be just rerolled freely. So Do make the unsocket recipe expensive enough that it's not worth it to most people.
Summary: make something harder or expensiver? Yeah sure! Make something impossible? No.