It's not that your Honda can't (edit: actually their specific model can't, others from Honda can), its that Honda didn't want to enable it under 20 miles an hour because they want to discourage use off highways. I wouldn't be surprised if your Honda has a similar to AP1 Mobileye sensor in the mirror, I know my Volt does and Chevy intentionally limited engagement to 15 mph and up even though once engaged, it can work down to 1 mph. There are Hondas with AP style autonomy via comma.ai and that's just supplementing the sensor set with an Android phone and some basic CAN bus access.

Tesla's "innovation" is being willing to ship "beta" features for better or for worse.

It's not like Chevy couldn't have used the same data it uses for LKA to do lane centering, by as Tesla has shown, doing that can cause "wrong" steering outputs (I.e. ones that would put you in a ditch), and opens up the system for abuse by the driver.

Where as only using it for LKA means when the sensor is "wrong" the worst case is a wrong LKA warning instead of doing what Teslas do on "fail road". And you can't abuse LKA easily. I've noticed my Volt seems to be tuned so that if you try and abuse LKA and let go of the wheel, it'll take longer and longer to apply corrective steering, causing the car to "ping pong". But if you hold the wheel and intentionally try and pass a line with firm, but wrong steering input (as you'd expect with a distracted driver), it will smoothly guide you along the lane as precisely as a human driver would.

To me Super Cruise is a more major innovation than Autopilot. AP works in more situations but the situations it works in, that Super Cruise doesn't, are situations where AP is notorious for having bugs that vary from inconvient to downright dangerous. It reminds me of how people compare AP to other equivalent systems like Distronic + based on disengagements, ignoring the fact that more disengagements can be preferable if it means avoiding events where there isn't a disengagement but the system is wrong