[DEV Question] Why is this allowed?

[Nestama]

My idea : change the ratio between weapon damage and the main stat and...that's it.
Because, again, your idea doesn't change the fact that the weapon is way too important compared to other pieces of gear.

You realize that they changed main stat weight for tanks and that the world didn't crumble ?

That's a pretty bad idea. The weapon is important because it's a weapon. Miste has the right idea of making it so that if your weapon level is below the contents level, then you should not be able to enter.
If you remove the importance of the weapon, then why bother doing the Anima questline?