Well, that's a big part of the issue, but it's also a fact that digital signals can be received with little degradation to a certain strength (depending on the receiver), but then reception drops off much more sharply. So if you're way out there, you might get pretty bad analog reception, but still put up with it, and then get no usable reception on digital at the same broadcast power.

Of course, the solution -- assuming the station is broadcasting digital at full power, and you still can't get it -- is to get a better antenna, which would have benefited your analog reception too. But honestly, I think my tendency would be to replace TV with internet, rather than spend more on an antenna...