I was speaking with a friend about this (whos Dad owns a few Renault dealerships). He was saying that yes it meets lower emissions etc and so becuase more cost effective, but the main thing is to try and target a bigger audience and attract new customers. Alot of hot hatches now are Turbo / Super charged, only ones i can really think that arent are 197/200 and Civic Type R (believe the new type r will be charged and they are trying to make one of the most powerful hot hatches) so Renault Sport are 'following suit'. My friend was saying that obviously the Clio RS community is just a tiny proportion of the whole hot hatch market. Current and previous Clio RS owners love the whole high revving engine and driving experience the clio RS offers and by making the chages they have done, may upset a select view in that it may be seen as the 'Clio RS routes' are being lost, but it allows them to enter the whole bigger market of turbo hot hatches and attempt to gain a whole number of new customer which would out weigh the number of exisiting Clio RS owners who would not be buying the new one.
I personally think the new one looks to big and for me the 200/197 are my fav (not be biased as i have a 200). Seeing the new one in person / having a drive may change my opinion, but for now, only going on pics i've seen.