It has certainly taken away hugely from the lustre of the Heineken cup even if some of the games have not returned to FTA TV.
I think it was lapsed poster Sidney who had a great post about the Munster team of the early 2000s who really brought the Heineken Cup alive on this island and to the masses and their demise coupled with the move to behind the paywall was a bug blow for the competition and its popularity in Ireland with the casual fan.
The six nations really benefits from its position in the sporting calendar in winter/early spring and saturday afternoon and evenings when there is little other live sport to contend with aside from horse racing for the casual fan to watch - if it goes behind the paywall it will certainly lose that unique selling point.