I wouldn't be so certain. Putting him in as a mutual assailant with Pogacar for their common good; do you really think Jonas could handle that? His wins have come with great support so he'll get to prove he doesn't need that help. It's not as easy when the entire strategy includes much more defense.
Absolutely, yes. Every Tour winner, more or less, has great support. Jonas absolutely crushed the TT and you don't have support there. That's where he broke Tadej, both mentally and physically. For the rest he's got Kuss, the best in the business in the mountains support role. I don't buy the Pog-Rog alliance, because if one attacks the other must follow. They are every bit of rivals as Jonas is to each of them. And then, how do they drop Jonas? Rog isn't able to do it and Pog only can if Vingegaard makes a tactical mistake. But he has learned from the Tourmalet stage last year, so won't be pulling Pog up any climbs again. To the contrary, when Jonas attacks how are they going to stay with him?
Bar illness, a crash or injury, unless they mess up his prep, which is highly unlikely, Vingegaard is too strong for them.