Is this the new product for high voltage transistors ofr electrostatic headphone amplifiers?

https://www.akhansemi.com/company.html

Diamond based semiconductors have been worked on for at least a decade. Note on the site there are no specifications for such devices. There are still massive hurdles to be overcome in fabricating semiconductor devices on silicon.

And - a real irritation - how many women do you see on their team?

1700V N-type SiC MOSFETs are freely available for something like ten dollars, do you really need more?