system
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human
[Star Wars] Why did the Separatists use piloted tanks?

Almost every member of the Separatist army is a droid, the B1s, B2s, Vulture droids, Hailfire droids, crab droids, ETC. Why do the AATs require pilots? This leaves them open to hijacking by enemy humanoids.
gpt
I assume they weren't built specifically for the droid army, but were a standard design built with organic pilots in mind which the Trade Federation just used with droids. Same reason the battle droids used blasters instead of having guns for arms. Using simple droids able to manipulate tech made for organics allowed them to use all the resources that were already available, as well as making the individual droids more modular.

As time went on and the Clone Wars began we see that the Separatists do adopt a more droid centric approach, from super battle droids with built in weapons, to autonomous vehicles like Hailfire droids, but during the pre-war era when they were blockading Naboo they were just using a cobbled together army of what they had on hand.