If RNG must be a part of this (which i prefer it not to be), at least let it be based on ruining the gildings themselves and not the equipment- the required effort to make a decent piece of gear is far too high.
Let's have base equipment, each item should have a base amount of slots
For example, leather chests have 1 slot, and steel plate have 3
At each respective quality increment, the equipment would either gain one additional slot, or an increment based on it's base slottage.
So, a 90q leather chest would either have 3 (+1 for 40q, +1 for 90q), or 3 anyways.
And the 90q plate would either have 5 (+1 40q, +1 90q) or 9 (+3 40q, +3 90q)
Gildings can be attached and removed only a certain number of times before ruining a gilding slot (or, perhaps removing a gilding deals wear damage- though the issue now is equipment without wear).
Creating a guilding should have a range, for example Bone needles could have 7~12 stealth at q10, meaning at q40 it would be 14~24, at q90 it would be 21~36. That should be the "rng" aspect of it, providing a stable increase in quality for equipment, while people may stay remake and reforge to try and get the best they possibly can.
It still favors people with more resources- but isn't as horrifyingly punishing as the current system, and won't call for remaking gear hundreds of times over and over.