I think their model is acceptable and sustainable. It's MIT licensed, and they make money on the self-hosted enterprise edition that gives you SSO, permissions, audits, etc.

Recently switched to it after going through most of the alternatives, because it has a clean UX, works on every OS without install, and has all of the features I need.

I'm gonna be a cynic here. Maybe they have a sustainable model _now_, but there is no telling for how long the VCs will be happy with the revenue this model generates. Somewhere down the line they might want to see a better ROI that involves converting Hoppscotch to a cloud-only app just like Postman and Insomnia

The VC is OSS Capital, so I'm not too worried about this happening.