If you really want to do something like that, you could always connect an Arduino or RPi (or similar) to a PC over serial/USB. Then you could use it as a kinda-gateway device. Taking commands from the primary PC and interfacing with low level peripherals over i2c, etc. But for the cost of this, it would probably make more sense to just wired the gateways up directly to Ethernet to allow one system to control all of the devices... which is how I imagine most factory automation is done. No need to have an extra PC to manage network control when an Arduino can do that by itself.
Aside from the hobby aspect, one reason why Arduino and RPi are so popular for these types of projects is that they are effectively cheap enough to devote to an individual project. You’d wouldn’t want to devote an entire PC just to manage a sensor or control a door, or... but an Arduino for $10 or RPi for $30, sure.
Aside from the hobby aspect, one reason why Arduino and RPi are so popular for these types of projects is that they are effectively cheap enough to devote to an individual project. You’d wouldn’t want to devote an entire PC just to manage a sensor or control a door, or... but an Arduino for $10 or RPi for $30, sure.