Many automatics these days are manual transmissions with a computer controlling the clutch. They have nothing in common with the slushboxes of old, the oil is just for lubrication.
Even slushboxes tend to aggressively lock up the torque converter. It's usually only in a "fluid dynamics" mode for brief moments. (Except maybe on a gentle hill start)
Maybe in sports cars but the majority of vehicles still come with hydraulic autos or CVTs.
I mean, certainly the VAG group likes to use their dual clutch automatics, but "true" torque converters are still very common. ZF makes them for like a million different cars, and AISIN makes them for the Volvo and Geely group.
ZF 8HP is still a traditional torque converter transmission. Most high performance or high torque applications use that design. Dual clutch automatics or automated manuals can't take it.