You haven't hit a wall - you've come to your senses. There is no need to continually dump money into a hobby in order to enjoy it... and what's the point in continuous accumulation of items that don't really bring you joy? (Hint, if you call it an investment, you're deluding yourself.)
Pare down the collection. You'll hit a wall in that effort - finding yourself still with more than you want, but not wanting to let anything else go. That's fine... stop there. Enjoy the knives you have - whether by using, carrying, fondling, or just having. Consider the idea of maintaining a set number of knives - meaning that if another comes in, one must go. You'll probably find that, in many cases, the new acquisition will be the one that doesn't stay. (I don't like selling before a new arrival, because there have been too many times that the new arrival left me flat.)
I haven't sworn off purchasing knives, but I have become extremely selective & avoid purchasing on a whim. When something catches my eye, I find a reason to wait. Often, the knife is sold before I look back; but, if it isn't, I take some time to think about whether I really want it.
(*edited because my paragraphs didn't look like paragraphs)