Can I host a Discourse forum for free?

As a freelancer, absolutely can atest to TIME = MONEY!!

Your original point was well made!

On my biggest forum I’ve definitely poured more money in the form of missed earnings than it’s cost to run the infrastructure, I would imagine at least by a factor of 50x, if not more.

Then again, there’s no putting a value on how rewarding the hobby can be and how it contributes to others lives too?