Only the PC version of the original version of Resident Evil was unavailable. It had a Remake in 2003, a port to the DS in 2006 and AFAIK has been and still is available for purchase on PSN in PS1 form for PS3, PSP and Vita since 2009 and PS4/PS5 since 2022. That's not even counting all the sequels and movies. And the PC port is generally considered, not the best.

There's better examples like No One Lives Forever that have been stuck unavailable for purchase because of rights reasons but RE1 is arguably not that.