Yep, it lights up but doesn't switch at all.
Sounds like something is suuuper broken. Sadly that's not something I can fix for just a save file, but here's a console command that will manually switch the setting to be off. You can google how to enable the console in Renpy if you don't already know how. It's fairly easy.
Open the console and run the below exactly as written. It's case sensitive. (Ignore the name. I still think this setting is dumb lol)
persistent.AndYetSeverelyDisabledLesbians = False
Worth remembering though that this won't affect any saves that are already "purged". You can tell if a save is "purged" because if you hover over it in the load menu, it'll say "This isn't a very spicy save" or something.