Food for thought: Perhaps it wasnt't the money as much as Stripe itself being the barrier? Maybe you would have gotten better turnout with other payment options (especially for a platform like Trello, crypto like BTC/XMR might be more welcome than you'd expect).

> My biggest lesson? Charge early.

Can't argue with that. And even if you go free early, advertise it as "free trial during our early days" or similar. If you already plan on charging in the future, get people used to the idea of having to pay for it from day one even if you give it away for some potentially extended time. Proper free-tiers with expectations and terms can come later down the line when the pricing strategy is clearer.

People emotionally respond very differently to their free trial expiring ("it was nice while it lasted") vs having their previously free service being replaced with a paid one ("f this enshittified rugpull"). The difference is proactive communication and setting of expectations.