Well, how many iterations of a loyalty programme have they gone through. I vaguely remember "Gold Points" and don't know whether there was anything between that and Club Carlson. CC was only notable for having a credit card that was great for hacking 2 nights for the price of 1 but otherwise offered no benefits. So there's no loyalty pull towards the brand.

Many Radissons have been nasty since the 90s. The fact that they are still Radissons is also surely a failure of corporate management to insist on meeting standards. I may be wrong, but I also recall reading that far fewer CC hotels are franchises, meaning that corporate could be cheap on renovations in order to pay out more in dividends.

But yeah, I can't quite see why any half-decent hotel would want to remain as a Radisson...