How to find out if a brew or cask package is optimised for apple M1. There doesn't seem to be any info on the respective package pages.
Any links of a regularly updated list of native packages also would be very helpful
Go to https://formulae.brew.sh/formula/ and search and click on the package you want to check. There you will find
Bottle (binary package) installation support provided for macOS releases:
Check Apple silicon ( if it is supported Big Sur will be written ).