This also isn't true?
It costs almost nothing to patch drywall. You can also do this yourself. Unless the point they're making is "TVs are so cheap, you can mount a TV inside of the drywall for less money than it would cost to fix," which also isn't true.
I had to buy the sanding pole, the joint compound, the putty knife, and the paint the other day. A TV would definitely have been cheaper.
In America, all of that other than the paint is available at the dollar tree. You're looking at ~$7 to fix the hole (spackle, mesh tape, trowel, sandpaper, paintbrush) and $12 to buy a pint can of matched paint, as long as the hole is smaller than your fist.
Larger you would need to add in a $20 patch panel of sheetrock, a razor knife or other sheetrock saw (could probably use the bread knife in a pinch) and a hammer and nails, so closer to $50 all in.
https://www.amazon.com/toshiba-fire-tv-32-inch-class-v35-ser... is $75 right now. On Prime Day I saw a similar one for $35.
I can buy a flat screen TV from Walmart for $74. A handyman to come to my house is a minimum of $150.
So the parent comment is true, buying a TV is cheaper than hiring a handyman to fix the drywall.
VESA mounts and installation are not cheap
it's really an apples and or ciders comparison
that said, now I realized I have a door with two pictures screwed to it, because we punched a hole through it more than a decade ago during a house party, and that specific door is out of production, and it's the door to the storage room so it was (and still is) the perfect solution :)