I can confirm: downgrading to php 7.3 did the magic for me too.
As I said, charging for your work is perfectly fine and expected. You decided to make it free software but at the same time you clutter the admin area by placing those notifications, that’s not good. Anyway, it gets solved by uninstalling your plugin. Thanks.
This is annoying. If you want people to pay, then make it proprietary, it’s OK to charge for your work, but if you decided to make it freeware, then go all the way and remove the messages.
Imagine how the WP admin area would look like if every developer were to take your approach. You’re helping to clutter the area.
