Almost all of these projects fail for marketing reasons. They want more performance, cheap stuff, or legacy compatibility. They'll say they'll buy secure chips or OS's until some tradeoff is required with a desired application. Then, they cancel it and the supplier is left with a huge loss.
I hope you succeed. I also thank you for a detailed write-up that listed good offerings from your competitors. That's more honest and fair than most startup writing. ;)
With compute-oriented hardware, have you considered making a prepackaged, multicore version that runs on Amazon F1 FPGA's? Then, anyone could test or use it in the cloud.
That would be too expensive for basic, web/app servers to use. However, some companies might use it for database, key servers, or (defense market) high-speed guards which already cost a fortune.
With FPGA's, one might also make load balancers with firewalls and SSL acceleration because they'd be comparing the price to SSL accelerators. Also, gateways for AI interactions which are in high demand right now.
(And a very good question, to be answered at a later stage.)