It appears API rate limiting has effectively killed these alternatives. You essentially get nothing but “Too many requests” 429 errors.
Lemmy sadly does not have the active niche news and discussions I want. But now nothing can be read without going to Reddit. I hate Spez
Go to the settings, ping the instances, and add a handful with good ping.
I cycle through 3-4 instances using the keyboard shortcut (Ctrl + Alt + L is the default but you can change it via your brower’s extension settings) and usually find one that’s up and running.