Okay so say I believe you. Why do you think a large majority of third party devs shuttered their projects they worked on for so long if it was just as easy as adding a subscription fee? Why didn’t more of them do it? I know of one that actually implemented a subscription. If folks were actually doing much less than 1000 API calls daily then you’d think most devs would have gone that way right?
There is no need for an actual installed adblocker. You can simply change system wide DNS to block ads. You can really use any DNS you choose, but I’d suggest mullvads DNS.
https://mullvad.net/en/help/dns-over-https-and-dns-over-tls/
Look for “private DNS” on your phone, or switch it on your browser if on desktop.