In the Olympics you have Nordic Combined, however, they have the events of Ski Jumping and Cross Country separate, as well. I can't speak for everyone, but I have never watched a Ski Jumping event and said, "Wow, that's really water downed, they don't deserve to be on an equal pedestal as the Nordic Combined athletes."
I see your example. But Ski Jumping and Cross Country are actual sports on their own. Non-Tumbling isn't a separate sport, it's just a cheerleading routine that's missing the tumbling. The best cross country skiers compete in the cross country ski event, not in Nordic Combined. If we're comparing this to cheer, it would be like saying the best stunters do the NT division instead of a division that combines tumbling+stunting, which isn't the case. The stunting in NT is no more advanced than that in a "regular" division. NT teams often consist of Level 4/5 or 4.2 kids who are just moving up to Level 6, or athletes who are too injured or don't feel like doing a full routine anymore. NT is pretty much the same as a regular routine, they just leave out all the tumbling
Nobody is saying NT teams don't have skill and that it's easy to do a routine where there are no breathers during tumbling sections (many tumblers would disagree that these sections provide a breather). Surely there are some fantastic NT teams with great Level 6 skills, and it takes a lot of stamina to do a Level 6 NT routine. It's totally understandable why this division was created.
But there are also legitimate concerns about including this division at Worlds. Tumbling is a huge part of Allstar cheer's identity--- it was a big reason why kids left their School/Rec competition teams starting in the 1990s to join Allstar gyms where they had access to spring floors and trampolines and could learn to tumble. Keeping kids motivated to do Level 6 tumbling skills is important, unless we're okay with the sport possibly going backwards long-term. Some people might be fine with that, I understand. It might help keep some kids in the sport, but it will also surely chase some out. There are differing opinions on this. I'm sure there are plenty of boys, especially, on NT teams that can do fulls, etc, and it's just wasted talent when all their gym offers for Level 6 is a NT team.
There is irony in that the easiest way for a lower level athlete to get to Worlds is to just stop tumbling all together. But I'm not too concerned right now about how NT might affect cheerleading as a whole long-term, because as long as only 3 teams from the US advance to Finals in the NT divisions, there's still a big incentive to enter a "regular" division instead.