You do realise that the distracting also applies to your fellow cyclists? Which isn't good.
I am also a "fellow cyclist"
I've no issue with riders asking other riders, in a group, to turn off a flash.
Other circumstances are less clear cut, for example if riding alone another rider catches up with me and finds my flashing light annoying I'd expect them to continue past me. They cannot expect me to change what I am doing just because they want to wheelsuck. How would they even be sure I am on the same event?
I'm 20 years of near daily commuting I've had two people ride up from behind and have a whinge about my flashing light. One of them I'd just flown past on a fixed. He buried himself to catch up with me for a whine. Really odd behaviour. I would have been out of sight in seconds.
The second time was on a cyclepath. A rider came up behind me and sat on my wheel. I moved over and waved them through. They sat there, then when we got to a junction had a whine. Both these were in full daylight.
m. Both were treated to a rare lack of diplomacy on my part.
Some people just like complaining. And for clarity, I don't mean you. Flashing lights in groups of riders are annoying and unnecessary, and I agree with you.