Out of curiosity, one user did try Chromium alongside Brave and said Chromium was not affected (forgot to ask them what version of Chromium they tried), and the users here are saying the mouse is fine, but the touchpad is not, but like that ticket, one user DID force X11 and said it worked while others didn’t.
One specific detail however is this:
Users here are saying the mouse is not the issue, only the touchpad. The Chromium issue is a reverse uno of this, that appears to be the mouse, not the touchpad (however, same oddity, forcing X11 worked for some like the other user here).
EDIT: Nevermind, found one user there who DID report touchpad issues:
@Mallakin when you tested Chromium, what version of Chromium was it?