It would be nice if everything in life was magically free. Sadly, software developers and many others need to make money so they can continue to develop things and even live.
I’m very happy to get something for free here, although I know it won’t last forever. Cars don’t, food doesn’t, memories of a big concert or night on the town fade. Most of the very good programs that appear here come around again. It’s taken me about 2 months to restock a new PC with most of the “essentials” from SOS. A 6-month or 3-month license is indeed a demo, try it and if it’s that good then you can always buy it, or wait for it to come around again. In that 3-6 month timeframe, or even a year in some cases, you should know if it’s worth the money.
If you want to complain about something, then ask why so few programs uninstall without leaving fresh cobwebs all over your PC. That should be illegal, and it greatly adds to the risk of trying anything new here.