Of course it's a gimmick and judging by the lack of many of the dedicated gravel types on the startlist it might be a bit premature to set up a World Championships, but it gets plenty of people a chance to get out and do some endurance riding without the risks attached of open road riding or the extent of technical requirements and challenges of CX or mountainbike, so it certainly has a role to play, but to date I've found it hard to shake the feeling of it being a sort of off-road road racing, or a massively simplified XCO MTB, that is good for participation but does tend to cater to the perception raised above that it's kind of a non-specific middle-ground for riders who either haven't found a niche or haven't made the cut in any one major discipline, and part of its appeal at the moment is how unregulated it is, so if the UCI are going to be stepping in and creating a formalised circuit, they run the risk of strangling the very thing that makes it appealing.
I kind of think that if they're going to go that route, they should have gone with the real length element of it, though, and made it like a 200-mile race for sure. I feel like gravel in the world of professional cycling at least should fulfil a similar kind of role to what Worldloppet does in cross-country skiing. Worldloppet has a mixture of professional and amateur competitors, men and women alike, all competing on the same course at the same time (with the elite women given a headstart, so the best women often hitch a ride for part of the course with the elite men when they are reeled in, adding a further tactical element which also increases the possibility of earlier attacks), along courses which are often narrower than those used on the main cross-country calendar (as almost all races are in Classic and often trails can be only a couple of tracks wide), and are usually of the kind of length which is as long as it gets on the World Cup or even longer (topping out of course at the 90km Vasaloppet), but the counter to that is that Worldloppet courses are often much flatter, with a couple of smaller obstacles or signature hills, rather than the constant ups and downs of regular World Cup courses.
If gravel as a discipline went along similar lines, so it had a top level circuit with some pro teams specialising in it plus occasional ringers coming in from pro circuits in other disciplines (like seeing Kowalczyk or Sundby rock up to Birkebeinerrennet) and amateurs taking place alongside, on real distance courses that gave it a point of differentiation and helped give it some uniqueness as a discipline, that would be grand; the comparatively easy height profile and lack of super-tough technical MTB-style challenges makes it more accessible to beginners and the endurance required to contest over the long distance will beget a new specialist type that is not really catered for in current pro cycling.