Inkscape lets me adjust kern of each letter because the curve can cause letters to touch.

On the contrary, I would say this is increasingly unusual nowadays. There are print restrictions on e.g. iStock content, but there's no attempt to "ration" the number of visitors that see a stock photo at a specific price point.

It's something that's generally put me off from licensing paid fonts - despite the work that has gone into them, because you're almost signing a blank cheque and it's not easy to know how many visitors are scraping content for LLMs.