A lot of the actual, serious ones that knew what they were doing got caught. Some went to lulsec to be jerks with no agenda and were caught by the Feds. All that was left were script kiddies that downloaded the Low Orbit Ion Cannon and used scripts they find online. Then they left or were overtaken by alt right idiots.
The original Anonymous are in their 30s and 40s by now. Everyone ages out.
Yep, that’s exactly what it did. Maybe there was a way to do it, say if you had a VPN, but people picked up pretty quick to ban a single IP.