It will come at huge cost, increasing price of phones (gotta absorb R&D and production cost). Only companies specializing in modems make money from their production.
And good luck with entering that market and not infringing on some patents.
They'd be better off with making a joint venture with Intel.
You have successful platform (iOS), that you make obscene money off. So gotta let your suppliers profit too. I get that Broadcom wanted big piece of pie, but thet's where competition come into picture.
It is going to end up like their self driving car. All money in the world does not make you best in everything.