It's the way things have gone. There's no 'just' about it though. Long-term it will marginalise cricket. Whoever thought it was a good idea to take it away from the mass audience is a fucking idiot.
It's not just me who thinks this. Ritchie Benaud talks a lot of sense about these matters, and in Australia, in many ways a more capitalist place than here, all important cricket matches are free-to-air.
In Australia, SA and India legally all major test series have to be avaliable live on free to air TV. Meanwhile in NZ and the WI Murdoch has the exclusive live rights. Which level do the ECB want England to be on?

mad: at the BBC going to the news headlines when Graham Gooch was about to make his triple hundred at Lord's). The Olympics and F1 could cause a problem, but they could just move the cricket to BBC2 or behind the red button when they're on.