<< I can literally connect my MacBook to my ipad and use it as another display for whatever I want >>
Yes, you can make the connection, but NOT for 'whatever you want' unless you accept lower signal quality. It is perfectly adequate for slow-to-change data such as program listings, spreadsheets, and stock quotes. But that connection is not a Hi-color, full-motion Video connection, and you will see dropped frames and/or a major decrease in video quality and/or decrease in number of colors in the images when you connect it that way.
Full-motion, Full-color Video is THE highest data rate of anything you ask a display to do for you. The cables that support it properly use tuned dual-rail Driver and Receiver circuits and are limited to under a Meter in length.
You are not providing anything even approaching the 32,000 M bits/sec pathway provided by an appropriate ThunderBolt or USB-C cable used for full-motion video at high resolutions if you connect it that way. You can't get those data rates 'over-the-air' using high-end fast 1,000 M bits/sec Ethernet or Wi-Fi.
Accepting external Full-motion, Full-color Video at those ferocious data rates and displaying it properly is a very difficult job for any electronics system. You would need a purpose-built device ready to accept and display those signals directly. The MacBook Pro is not built for that purpose, and my answer was never intended to be an arrogant jab at you, just the facts.
The ideal device to support such a data stream would be a TV set or a stand-alone display. There are some good, affordable device on the market now that were built for that purpose.