All the methods I see around cloning your old drive to your new one require an enclosure of some sort, I don’t really want to pay for extra hardware for something I imagine I will only ever do once. Is there any way to back up my SSD to my windows machine and then load it onto my new replacement SSD? Or is this a bad idea/should I start from a OS install?

The main reason is not so much the downloaded games, it’s more stuff like saved persistent decky powertools profiles, some non-steam games I’ve added and had to spend hours configuring to work properly, some other configs I have for some decky plugins like css loader, notes, etc.