1. Do we still need to enable removal of released flow version via support separately, if we enabled few years ago generic 'remove components from managed package' permission and have been able to delete other type of artifacts from our 1gp so far? In other words, does SF introduce new 'permission' specifically for flow version removal or is it covered by general permission to be able to remove artifacdts from released managed package?

2. Regarding flow removal automation. It seems like 'sfdx force:data:record:delete' command support filtering condition as one of its many keys (-w). Potentially it seems to be possible to do clean up with just one command, somehting like this:

sfdx force:data:record:delete -s Flow -w "Status=Obsolete"