Re: Unique Content
"They had 625 lines instead of 405. But required purchase of new TV and aerial."
The killer there was that UHF sets were on sale for a long time before VHF was turned off. That meant that there was a long time when the broadcasters were supporting two systems. The switch-over to digital was handled by having digital to analogue adapters available and also dual-standard receivers so that the analogue only sets could die a natural death without being unusable.
The TV analogy is also limited in application because on the whole in a household with multiple sets each one could go irretrievably TITSUP with out affecting the rest. But throw in a mixture of IPv4 printers in a domestic situation and the occasional box that absolutely has to run XP in a commercial situation and the TV analogy doesn't apply.