I think what we want to compare here is "show grants" vs "show effective grants" so this doesn't make sense to me on that page: "SHOW EFFECTIVE GRANTS output before the change:", because SHOW EFFECTIVE GRANTS is a new command so I don't understand what it means "before the change". The same is with "show effective grants after the change". I might be wrong here so take this with a grain of salt and maybe check with .
This page for PS 8.0 is wrong:
https://www.percona.com/doc/percona-server/8.0/management/extended_show_grants.html
In this ticket the command has been changed: https://jira.percona.com/browse/PS-281
So the new command is "SHOW EFFECTIVE GRANTS;"
If you use just "SHOW GRANTS;" like in the last example on the page you will get upstream behaviour.
Here's how it looks on the server: