I’ve done the route you’re talking about a few times, including once with my 10 year old son. That’s not to say its easy (we took ages, I was right behind him, we had rests on slings etc), but it isn’t bonkers IMO.
I’d 100% do it, it’s a beautiful route with good condition wires/bolts. There are 3 sections, increasing in challenge and each has a retreat walk you can take if you don’t fancy the next section. As such the first section is a good qualifier.
It does get very hot and very busy so I’d aim to start really early, so it’s nice and cool and quiet. You won’t be rushed then by faster people Catching you up, with my son we started at 8am and had it to ourselves until the very top. Its about a 10 min walk from the huge car park.
If you enjoy it then the one up the other side of the valley, at the Cormet de Rosalend) is amazing, it’s on/called the Rock du Vent. Again an early start makes a massive difference and you definitely need good weather, but on a good day it will be the best thing you do on holiday. This has a longer walk in, about 45 min from memory.
I’m jealous! Have fun.