I think most of the answers to your questions can be answered by the question that this comment section is responding to, to understand the framing that I'm commenting in:

What's different about this time and with Lemmy to make it a feasible alternative to Reddit? Is it random chance?

But, this is the first and last Reddit related thread that I plan on participating in, so I'll be cheering with you, if we ever get the miracle of reddit evaporating. Although, I would be worried where they would all end up.

It's the first one where average users were affected beyond the blackout, though.

I think this makes the very big assumption that the average user uses third party apps. All of the polls on reddit, that I saw, suggested this is not true. For example. If that's true, then the average Redditor is only being inconvenienced by the blackout and related shenanigans.

Was there a wider poll that showed non-negligible third party usage?

I'm seeing red whistles and hearing dog flags coming from you! Am I doing it right?