I don't think that's true. Insomniac was already working with Sony on Spyro and they got help from Naughty Dog for the first R&C.R&C (or, more accurately, a project that morphed into it) was pitched around the industry and Sony picked it up. What different is that from Microsoft selecting a 3rd party studio to make a new Flight Simulator?
I can't find anything that say it was shopped around. It seems you just don't want to give any credit to Sony so you make shit up? Why?
It says here the idea was shown to Sony and Mark Cerny to get the greenlight to make the game.
Ratchet & Clank (2002 game)
Ratchet & Clank is the first installment in the Ratchet & Clank series developed by Insomniac Games and published by Sony Computer Entertainment. It was initially released in November 2002 for the PlayStation 2 and re-released for the PlayStation 3 in June 2012 and PlayStation Vita in July 2014...
ratchetandclank.fandom.com
I never mentioned Flight Sim so I'll let the other poster say what they meant.