The very beginning of this thread is already based on a confusion, which the OP themselves apparently failed to grasp. "Flashing mode" and "strobe mode" are two fundamentally different modes of light operation. And the OP mentions both in the original post and thread title, which makes it completely unclear what they were intending to talk about.

Flashing mode, if named properly, operates under nominal light output levels. These output levels do not bother anyone, regardless of whether the light is flashing or not. They don't "hurt" anyone's eyes ant more than a steady light would. If someone experiences any kind of debilitating reaction to a bicycle light operating in flashing mode, this is indicative of a major medical condition, which in most cases immediately disqualifies such individual from operating any kind of vehicle on public roads. Moreover, depending on local laws (in my case I'm referring to driving code of a specific US state), in such cases one might be required to self-restrict themselves from operating vehicles on public roads without waiting for any "official" order directing you to do so. Under certain circumstances one can be held criminally liable for failure to self-restrict.

The front light rules are pretty simple:
1. Avoid using strobe modes without a very good reason.
2. Daytime riding: flashing mode, always, no exceptions.
3. Night riding: steady mode, preferably with proper beam shape (i.e. cutoff). Might be accompanied with lower brightness flashing markers.
4. And don't worry about anyone whose eyes might be "hurt" by regular flashing: 99% of these people are just feigning "the princess and the pea" syndrome, the rest have no business being on the road at all