What the title says. I've played several games with 4.0, and there are some ship types that were very common in 3.0, but I haven't seen the AI use them at all in 4.0. Anti-Armor ships for instance. AI has never had them unlocked, the Eye never spawns any of them, etc. Could be the same with some other ship types too, like Raiders and Raptors, though I think I've seen a few of those, but not a single Anti-Armor ship, that's for sure.
I'm using Complex ship types for my games, so I'd imagine Anti-Armor would be included.
Just freaky weird luck?