Antitrust nowadays is just a buzzword politicians throw around every couple years in reference to household names like FAANG in order to get reelected. Unless your average grandma knows the name Nvidia, don't count on those in power to even pretend to do something about this.
Why? From where I sit there will still be plenty of (or at least no less) competition in the CPU/GPU space--especially considering the fact that ARM itself is not a semiconductor manufacturer.