If I were to use #Emacs or #Vim / #Neovim for #notetaking, is there any way to access #notes from the #browser? Perhaps through a #pwa?
Is there anything like #cloudmacs for (neo)vim?

https://github.com/karlicoss/cloudmacs

GitHub - karlicoss/cloudmacs: Selfhost your Emacs and access it in browser

Selfhost your Emacs and access it in browser. Contribute to karlicoss/cloudmacs development by creating an account on GitHub.

GitHub
@slashtechno If your notes are in a git repo, why not just push them to Github? You then have desktop and mobile access (browser or app). If the notes are Markdown, and you care more about having access than specifically using the browser for access, you might like Obsidian better - I use Obsidian's iCloud sync, but there are other options. I often edit my Obsidian vault in Neovim, rather than using Obsidian's client.
Give Up GitHub: The Time Has Come!

Those who forget history often inadvertently repeat it. Some of us recall that twenty-one years ago, the most popular code hosting site, a fully Free and Open Source (FOSS) site called SourceForge, proprietarized all their code — never to make it FOSS again. Major FOSS projects slowly left SourceForge since it was now, itself, a proprietary system, and antithetical to FOSS. FOSS communities learned that it was a mistake to allow a for-profit, proprietary software company to become the dominant FOSS collaborative development site. SourceForge slowly collapsed after the DotCom crash, and today, SourceForge still refuses to solve these problems0. We learned a valuable lesson that was a bit too easy to forget — especially when corporate involvement manipulates FOSS communities to its own ends. We now must learn the SourceForge lesson again with Microsoft's GitHub.

Software Freedom Conservancy