Self-driving car companies dont want a unfiied signalling platform or other "open for all" infrastructure updates. They want to own self-driving, to lock you into a subscription on their platform.

Literally the only open source self driving platform, from trillion to billion to million dollar companies is comma.ai, founded by Geohot. Thats it. Its actually very good, and I bet they would welcome these upgrades, but that would be a consortium of one underdog pushing for them.