Needs must, I suppose. The weaker rider will have to look for opportunities to claw back time they lost through lack of ability on climbs. I suppose that is why you rarely see them on truly challenging events....although of course one person's nice day out is another's challenge.
A lot depends on size. Riding all day in the wind is no big deal to a big rider from the plains, the kind who dominate Paris-Roubaix. The cooling effect of the wind enables them to shed the heat that comes with power. I had my highest heart rates bridging to faster groups on flatland Audaxes.
The reverse is true in the hills, as power is accompanied by low speeds, with low cooling effect. Extreme thinness in the likes of Froome brings the advantage of less weight to haul up the hills, but it also brings more blood vessels into closer contact with the skin. A taller rider can't get rid of the heat as well as a smaller one, as volume is a cube function, while surface area is a square function.
So the spectating experience is different for a rouleur. Part of the interest is in seeing how close to cracking the 6 foot + GC contenders come. This year's Tour has the least solo TT miles since 2015, and the second least since 2000. So the Froome model of a strong TT rider who's stick thin to manage the climbs might not suit.
The Peloton contains a number of competing constituencies, and it's partly up to Froome as the Patron to accommodate them all. That's also the role of the UCI rider's rep. Jens Voigt filled those shoes for many years. It's currently Bernie Eisel, who's not riding this Tour. I wonder if anyone deputises for him?