TV is fine, it's just the way it's consumed that is changing. And British TV is something that could do with a little help given how it's dwarfed in size by the likes of Netflix.
BBC iPlayer now has box sets of old series on it, to cater for the binge watch concept, but live event TV seems to be in decline except for one or two shows. And herein lies a problem - something like The Last Kingdom got modest audiences when first broadcast, but gained popularity globally via Netflix, who then outbid the BBC to take the third series exclusively. They can't compete with that.
I've mentioned before that the concept of a UK online TV platform to cover all the channels was shot down on competition grounds, but piecemeal as it currently is, they don't have a chance against Netflix and Amazon. Time to re-visit that one I think.