The rust community is its own worst enemy. The political infighting and constant compulsion to shit on other languages is a turn off to many, and there are plenty of applications where memory safety is not the highest priority.
In this case, the issue is really the C kernel devs, not the Rust devs. Some are not open to new ideas at all. Take a look at the conference video he linked to for example: https://youtu.be/WiPp9YEBV0Q?t=1529. He clearly states that he's not trying to make the C devs learn Rust.
I've seen the video and I agree with Ted. Anyone with experience understands creep, and although Wedson denies it it's exactly where they're headed. Ted and others are right to voice these concerns and attempt to set very clear expectations for the rust developers.
They took on the task knowing it was experimental, would be difficult, and that they would be second class citizens - you don't get to agree to the terms and then complain about them later.