I noticed this the other day when I installed VSCodium on my new Windows box. I had a functional setup for one day , then the next day I couldn't install a language extension I direly needed. It's left a very sour taste in my mouth. I've used Emacs for ages and despite being a much more niche editor, it's never been so hard-dependent on centralized repositories, and the centralized repositories it does have (ELPA/MEL…
I feel that you're conflating few concepts, hackability, "open source", single point of failure architectures. Yes, VSC is less hackable than emacs, but I don't think it's necessarily the same thing. VSC (and others like it) are going for a more streamlined "App Store" experience, while emacs is going for a more DIY/hackable style editor. You can always fetching the VSIX file and sideload it is if the "store" is down…
I expected it to be a little less convenient to leave Microsoft's beaten path. I did not expect it to be a massive waste of time. This is what I meant by futile. Not only is it apparently very brittle, it's missing large swaths of VSC's ecosystem. Hell, I don't even know if the extension I wanted is available on OpenVSX because it's still down!
If Microsoft hadn't openwashed their product, I wouldn't care nearly as much.
Besides, Emacs still provides a streamlined system for managing packages on top of being hackable. It even makes installing and upgrading packages straight from a Git repo easy. Sometimes you can have your cake and eat it too.