[king-of-turtles]

A lot of OSS founders make bold claims to their contributors and donors like "oh we'll never take XYZ feature away or charge for our services". Until they do.

It's fine to be proprietary. It's ideal for most business models that are products and not building blocks.

It's better to start as closed source, then go open if you feel it's a good route for what you're building. You'll piss less people off that way.