Completely agree. An interesting stat on the economics of broadcast: the BBC spends 12% of all its distribution costs on iPlayer, even though that platform is responsible for just 2% of the viewing.
It's not a cheap way of getting stuff to people - and of course, not only does it increase the cost for broadcasters, but for viewers too as they have to subscribe to some sort of ISP to get the content delivered to them.
In a piece I did earlier this year, I had a graph showing the efficiency of DTT vs projected increases in the capabilities of LTE; it's a long time before we'll be able to replace it.
And, of course, with mobile broadband, the operators aren't actually really interested in delivering your TV that way. They'd far rather people are using it to look at cat photos, or web pages, or anything that stops and starts, rather than consistently streaming video, because the latter actually means they'll have to invest massively in networks, rather than executive salaries and dividends.
If the DTT frequencies are lost, eventually, I suspect it will be the end of free TV, certainly in the UK, because the mobile networks aren't going to provide anything free when they can charge you, and the two most established platforms have pay elements anyway.
Without a free DTT system, many channels may decide that getting some - any - income from Virgin and Sky is better than staying with Freesat