I absolutely do think you should be concerned with your earnings. I'm not downplaying the change for you at all. But that's not the same as Medium should be the one to pay you.
Regarding the algorithm, it does not push articles in or out of the paywall. As I said before, there is a checkbox when you publish. That is what determines it.
As for "we can't pay [you] what we used to pay." I'm sorry, honestly, that that message didn't land harder. I'd said some version of the bar for quality is going up for more than a year. And I can see now that many people didn't think it applied to them.
Your statement that we can't pay what we used to pay isn't universal though. We now pay other people much more.
But if it helps you at least to have some clarity, "we can't pay [you] what we used to pay [for what you used to write]." I don't begrudge you what we had paid. But we were losing money on you. That's just another way of saying that we are stewards of our subscriber's money and now we know very clearly that we've taken a big step forward in how we invest that back out to the authors.