My commute is mostly on roads with cars. I don't ride as fast as I can. Driving defensively, you want to be able to break and avoid a collision.
I witnessed a really bad accident, where a car t-boned a cyclist. This has cured me of riding as fast as I can into work.
I see a lot of normal bikers as well as e-bikers going faster than is safe and I think e-bikes contribute to riders putting themselves into jeopardy.