Absolutely. I worked somewhere where we routinely had alarms go off due to botnets swarming us with weird (and obnoxious) massive download tactics (of publicly available user generated content, that is).
If it can be gotten by anyone, it will be gotten by LLM trainers.
Maybe. But if there were 10000 sent and 500 responses, that still isn’t enough information. You would need to know how many were even handled and perceived by the intended recipient.
But maybe you can work around this by canvasing in person rather than fire and forget.