If trump tries to trim down the monopolies it will only be in his favor.
I still won't mind because Microsoft faced a pretty big case over IE. It could do that behavior now and no one would stop them. Sure Firefox would care but I don't use their software anymore.
Breaking up Google would be a great start; then tackle the print giants and TV giants (oh and radio if it still exists)
Sinclair however makes trump happy so they are the first I'd like to see broken up.