Not the same thing at all. Parallel ports are obsolete, ethernet ports are notIsn’t that the same answer we got when PCs we’re loosing parallel ports?
The issue use that you are trying to use a laptop that doesn't have an ethernet port. There are thousands of new, modern laptops available with ethernet ports. You don't have to buy an old one.
What's the difference between a dedicated PC at or in your control box and a standalone control? The one with the dedicated PC can do more.