Side note: you could probably put ads in a Thunkable X project using a web browser element, and make it go to a GitHub Pages page that contains your ad. Not sure if it would work/violate any Ts & Cs (just a random idea) but could be helpful to pay fees for privatising your apps!
I’ve spent about 3 years on thunkable.
If you include last year, which I wasn’t active a lot because I was focusing more on Android Studio, then that would be 4 years.
If you also include the years I’ve spent on MIT App Inventor, that would be 6 years.
Most people using Thunkable are likely students who are still in high school and have very little income if any at all, or are university/college students who can’t even pay off their debt. I think the price for Thunkable Pro should be dropped drastically, especially with so much competition from other drag-and-drop app builders such as makeroid.