Devs have said they will review the case of Challenger 2. Nothing is confirmed. But things will be reviewed.
1 new tank does not suddenly render Ariete obsolete. Its still a very strong tank and remains one of the top tanks in game. Certainly nothing in this patch is planned.
US teams performance is for a number of reasons (also dont just blindly trust thunderskill as its not the full picture at all) and its not solely to do with the actual capabilities of their equipment.
But again, like the Challenger, the devs have said they will review their situation.