Think it really depends.
My commute used to be 9 miles of MUP bookended by roughly 0.5 miles of residential. I always turned on my light to the lowest flash or slow strobe or even steady so as not to blind other MUP users behind me, but it was far more important to have a headlight on the street since cars are going only slightly faster than me and have plenty of time to see me, however the same couldn’t be said about those turning into my path in front of me.
I also commute now by bike to multiple places for work, and in those more traffic heavy roads I definitely use a bright but slow flash still, I actually find drivers give me more room. As a driver I think the mentality here is that if it’s a crazy flash, no one wants to stay behind you for long and drivers can tend to get annoyed/aggressive.
if I’m riding in a peloton or group ride then it’s low slow strobe or nothing at all, the pack itself is visible to vehicles.