That said, I work with lawyers as customers and I suspect there was an adjacent market in data privacy that a hosted browser would have had PM fit for.
A lot of industries have strict legal requirements on controlling employee access to data (think healthcare, legal, compliance). In these cases, SaaS becomes risky if it can be accessed by anyone off their work computer.
The standard solution is to limit the webapp to be accessible on VPN, and limit VPN to be accessible on MDM controlled devices, and limit MDM to be accessible on company owned devices.
It would be a lot easier to just control the browser viewport and prevent data harvesting (essentially what Mighty was doing, focused on performance).
Sounds like a small change, but it makes a world of difference when it's not feasible to send a physical machine to someone (3rd party contractors, overseas employees, low wage employees, etc)... something I discovered when talking to lawyers about using contractors overseas for routine data entry tasks.
But that's definitely not the same kind of user, or tech expertise and would have been a big pivot in itself. Hopefully someone buys the IP and builds something cool.