Final update: After a slow start in the primary feeds and channels, I looked at every person on the rewards leaderboard. Yes, I looked at the casts of 3,000 accounts today. Across my entire search, I came across 203 users I wasn't already following and have <100 followers.

I viewed more than 4,000 casts and only found 37 casts that fit my original criteria. I've decided to split the $125 reward among those 37 casts using likes with Noice. Why so few compared to my goal?

Ultimately, I did not compromise on my original criteria:

(1) cast by an account I don't follow already,
(2) has <100 followers, and
(3) I find genuinely interesting.

I didn't intend to prove any point about the algorithm, and I'm not sure it does. I simply wanted to pay my rewards forward. But going down this insane little rabbit hole sparked ideas + questions for me about new user discovery here, which I'll share eventually.

For now, I'll include links to those 37 casts in a reply below.