Good question. Over the air TV is a hassle if you want similar functionality in your home. The technology to do something similar to YouTube TV is expensive and buggy.
For example: I stuck a giant antenna in my attic ($150), and then I bought an HDHomerun ($200), and their DVR software ($50,). Their DVR software has to run on some kind of a device, but I already own an NVidea shield, which it runs on. Before the HDHomerun I used a Tablo ($250) + ($150) hard drive. The Tablo, though, is a buggy piece of junk. Even before that, I used a Windows media center PC ($1500) that worked very well as a DVR, but Microsoft end-of-lifed their support for DVR.
So, for about $2300 in sunk cost I have a working, but buggy and difficult-to-use DVR solution, and two DVRs that are collecting dust. This pays for 5.5 years of YouTube TV, with no buggy software and no hardware to setup or collect dust when it's end-of-lifed.