I realize a while ago they changed it so parrots & ocelots spawned on grass blocks, not leaves. 20w14a said it fixed the issue of ocelots spawning (I have yet to see an ocelot spawn in my totally cleared out jungle biome, after afk'ing several hours). But, I know parrots aren't respawning either.

Before , back in 1.15, if you cleared a jungle so you had a big grassy area, within 30 minutes of afk'ing you'd have a few parrots spawn. I have a base in a cleared out jungle, on my server, and after 30 days of playing on a new map, at least 100 hours, all survival, still have yet to see a single parrot spawn.