Yeah. As some has said already PLC are more oriented to robotic arms in factories etc, where space is not a premium. Robots like anymal from anybotics, spot from boston dynamics or the unidog from unitree to name a few don't use PLC at all due to lack of space. Also energy efficiency, mcu at most will push less than a watt to move something complex, a motor control for the FOC, I mentioned earlier.

I worked for the past 4 years in HP siteprint.The main problem was developing all to fit inside a pelican case that you could check in on a plane. The smallest PLC was almost the full internal volume of the robot. That's why I said microcontrollers, more ready available to experiment at home, faaaaaaaar more cheaper and those two, very well documented. STM32 in europe is the big player but is harder to get into, the documentation tends to be cahotic.