Also, Figma and Framer are backed by venture capital. They're going for marketshare and don't need to make any money from licenses. I appreciate that the Subform authors are upfront about their position on the order page: they're two people who need to make a living, and you can choose to support that or go elsewhere.
The cost of subform is truly on the higher side. I understand that it's catered to a niche target group - how niche is it though? if it's managed by 2 people, 1000 customers would bring in $25.000 monthly before tax. I cannot imagine that they aim for 1000 customers only, though.
I tried — and failed — to make a living in this market with two products, Neonto Studio [1] and React Studio [2]. Reaching one thousand subscribers was a distant dream. Nowadays we just give away the base product, and the real business is focused purely on customizing the software for enterprise in-house development where the pain is much greater than with what one might call "competent teams" (i.e. practically anyone reading HN).
[1] http://neonto.com/nativestudio [2] https://reactstudio.com
Subform is in beta, and the others are finished and offer free trials.