How to Make Suitcase Fusion plugins work with Newer iMac, Adobe 2020 design programs w/out upgrading

Fonts will not currently activate automatically when I open files, so I have to keep writing down the font names that will not load, then search and manually activate each one in Suitcase every time I open a file with inactive fonts. It is driving me mad.

Specs:

Mac OS High Sierra 10.13.6 (machine is less than 2 years old)

Adobe Creative Programs - most used are Photoshop 2020 21.0.2 and Illustrator 2020 24.0.2

Font program is Suitcase Fusion 20.0.7 (8698) - non subscription based

When I go to 'Manage Plugins' in Suitcase, it shows that plugins are not installed, but also says, "Your plug-ins are all up to date!" in the bottom right on the dialog box. I asked specific questions via the 'help' feature with suitcase, but their response was just that I need to upgrade (which may be true).

According to Suitcase, I need to upgrade to their latest subscription-based program, the one I have is outdated (the one I have was purchased when I got my new computer less than 2 years ago). Does anyone know if it's possible to make this program work for me? OR, is there a better way to manage fonts without paying a yearly subscription? I have approximately 12,000 fonts on my machine...

Side notes: I used to work full time 6 or 7 years as an art director, when I had computer issues I had the IT guy deal with it. Now self employed and issues like this seem like a giant time suck to try and figure out, and not my strong suit. I don't do this type of work hardly at all anymore - mostly just do work here and there for old clients. I'm busy with a lot of graphic work in January, then the rest of the year there are only a few small graphic projects. Already bothers me to pay Adobe subscription all year when I hardly ever use it anymore - would prefer not to keep adding subscriptions. I just want fonts to activate when I open files that contain them...