I bet a bunch of them did some naïve calculation that said "because digital performs better, we can reduce broadcast power by X, for a savings of $Y, without lo

I bet a bunch of them did some naïve calculation that said "because digital performs better, we can reduce broadcast power by X, for a savings of $Y, without loss of range", but real-world conditions meant this actually did reduce their broadcast range a little (though mostly in low-population areas they barely cared about anyway). This may have coincided with lower investment in broadcast, anyway. Replacing the transmitting equipment, don't care about providing as much range as the much older, analog equipment did, because the per-viewer value has dropped enough that it's not worth it to reach rural areas, so you cheap out on both equipment & broadcast strength.