

I still use my copy of photoshop from time to time.
Photopea has been my go to alternative for opening actual psd docs for a while.
Paint.net was my go to for quick stuff back in windows. I’ve been learning Kirta on linux now.
But for certain work, the 10 year old copy of photoshop is still better at certain things. Specifically for editing actual photos (go figure).

Speculation to your question, for monitoring and control.
For monitoring, log temperatures and send error message if it gets too high. Data could be used if any legal question come up about food spoilage.
For control, I’m guessing there’s times you want to shut it off or enable/disable defrost. Easier to do that at a computer than have controls that are either a pain inthe ass to get to, or too easy for some moron to mess with.
That being said, it should be on a local network and have no access to the internet. However a chain store would probably want the data sent to HQ, so the computer would need to be on the network.