I track my time and have spent 570 hours since 2018 working on fbs. The vast majority of this (526h) was for the free version you are complaining about, the nice documentation etc. You are criticizing me for not giving you everything I do for free?
It's documented very well, extremely easy to use and the pro version is priced very well.
I was suggesting that, for you to make more $$$ from it, its better to provide a free trial period for the said version.