But the open ISA levels the playing field and allows for upstart hardware designers to make compatible hardware that is royalty and/or blob free.
Following the source code for the C910 core upload 24 hours ago, Olof Kindgren is live-tweeting getting it going in an FPGA using the existing FuseSoC framework. He made significant progress in the first session before going to bed. It would not surprise me if it's working in the next 24 hours.
That's a big "when". The road from an ISA to a core is long, and unless the core is copylefted (this isn't), then you aren't going to get the source code for something someone else manufactured either.
(2) having researchers with anonymous retail samples verify through decapping and inspection. I believe der8auer in Germany does die shots -- it would not be a bad idea to kick start this kind of research for community assurance purposes.
It's difficult to prove there's no hidden logic, but it's also not trivial to hide complex logic needed to introduce covert undetectable vulnerabilities (probably around things the RNG source or crypto).
Also assuming you're a high value target, otherwise this is mostly going too far.
And there is certainly growing interest in blob-free computing [1], so some at least will exist to fill that demand. There is some hope for video with Linux landing blob-free hardware encode/decode very quickly the last couple of years [2].
1: https://www.crowdsupply.com/mnt/reform/updates/post-campaign-orders
2: https://www.youtube.com/watch?v=E9JLxjYlIWg