Ways to make Big Sur run faster? Some users report Chrome and Firefox being slower on Big Sur

On a 2019 MBP 13 (16GB) ... everything is noticeably slower ... even native apps like Preview

This reflects my experience.
Other than waiting for updates to Big Sur, what settings can I adjust in the mean time to help mitigate any jankiness Big Sur introduces?
Some solutions/ideas found so far:

Downgrade to older macOS versions

References:

Google search for big sur stuttery
Update
This is embarrassing but I now think Big Sur wasn't responsible for the choppiness on my machine at all. I had installed Adobe Creative Cloud shortly after updating to Big Sur. When I uninstalled Adobe Creative Cloud 7 days ago the choppiness completely vanished.
Previous answer
This is not an answer, but may help someone else. For about 3-4 days after updating to Big Sur, the cursor lurched across the screen, keyboard inputs took hundreds of milliseconds to appear on the screen (meaning I'd sometimes hit the key twice because I thought the first didn't register).
Approximately 4-7 days after the update, the behaviour disappeared entirely. I have not been able to explain why it happened (it never happened in Catalina, and it started immediately after updating to Big Sur, so I presume the update had something to do with it). And I also cannot explain why it stopped, except that it ceased 4-7 days after the update to Big Sur, without me doing anything.