Have to say, this doesn't make a lot os sense to me.
Yes, the Super League Grand Final has surpassed the Challenge Cup final as the premier event of the year - but that doesn't mean you remove an event, it means you have two.
There are plenty of loud voices inside Rugby League that Super League is too repetitive (loop fixtures), regular season games are not meaningful enough (and the League Leaders Sheild not relevant) and has not had enough winners (just 4 since the inception of the Grand Final).
The remedy to that is not to remove meaningful knock-out games and a competition which has delivered Hull FC, Catalan, Warrington and Leigh as winners in the last decade over and above the teams that have also won Super League.
Blowout games are a part of every sport - they are nothing to be embarrassed about or to make knee jerk reactions from. The game between Warrington and St Helens was superb and a great advert for Rugby League, while the final last year was one of the most memorable occasions in British Rugby League for a long time.
Binning the Challenge Cup would be the biggest mistake the sport would ever make, luckily it is not going to happen.