Seems to me that businesses operate within an incentive structure that will always encourage them to take maximum advantage of users and do anti-user things no matter what their original goals were. The non-corporate part is key imo (see Canonical, Mozilla now etc.)
On Gnome, "Web".
On macOS, Safari may not pass your "non-corporate" requirement, but it's spiritually non-corporate, and functionally "just a browser". It's also wicked fast and extremely light on your resources.
On many platforms, "ungoogled-chromium" may satisfy your needs. It's under the name "eloston-chromium" in many repos. https://github.com/ungoogled-software/ungoogled-chromium
https://html5test.com/results/desktop.html
Looks like its the worst. Unless you have something proving otherwise. Till then I'll assume all your facts are bullshit.
Self-plug but my indie conferences [0] promote software that respect the user's quality of experience. One of my favorite presentations that we've featured is SerenityOS (including their open-source browser) which made headlines at the time. [1]
I'm trying to ungoogle and switched to Vivaldi without enough research. Its a really nice browser and I really like the community around it (like their Mastodon service), but I basically jumped from one corporation's browser to another.