Too many people appear to be confusing the idea of the sportive with its current popularity and commercial exploitation. Sportives have been around a long time and they will continue to be around if and when the current wave of enthusiasm dies down.
And much as I decry the commercialisation of sportives, I note that some people here seem to simply resent the fact that other cyclists enjoy a different kind of cycling to them, or indeed that cycling in Britain is growing, diversitfying and attracting more people, many of whom have apparently not 'served their time' as hardened commuters, audaxers or track riders.
There's no need to put up one kind of great cycling experience (like dell's FNRttCs) against another (like sportives). If there are problems with any individual kind of cycling, let's just deal with those issues in themselves and avoid the tendency to one-upmanship and 'my event is better than yours'.
How long do you call long?
The first I heared of Sportives was about six years ago when technology advanced to a stage where each individual's riding time could be monitored and logged.
IIRC, it was called a 'flea' which the rider zip-clipped to their bars.
Sportives in the UK are still in their 'honeymoon period'. Lots of enthusiasm for a relatively new type of bike ride.
And we all know what happens to Honeymooners,,,, they get fleeced by the locals.