In other words, we are pushing teams up to be the punching bag for upper division teams. How does this bring competitive value to the league?
I think players forget how much quicker you improve if you play against better competition. As someone who has been around for a while, advanced teams would get better MUCH quicker if they scrimmed invite teams and objectively looked at demos. However, there's this "winning only matters, can't wait to type .log and feel good about myself" and not a "Why did our push work? Why did it fail? What are the top invite teams doing as a default setup". There's also endless resources of streams/youtube/people to just ask questions.
The big issue though is that you fail to recognize that there are advanced teams that want to "seal club or smurf" in advanced. When winning is the only metric used for TF2, it promotes stagnation. People win advanced and refuse to move up or play invite, it's toxic to the main players.
I think improving to the point of being able to have someone else cut their main rostered player for you is insane.
But it happens.