What I don't understand is, if the Republican party is anti-competitive, why haven't they fought against many of the other monopolies that exist. The targeting of Google is... suspicious.

It’s pro “Big business”. Politicians pay lip service to “small businesses” but they don’t care about them. Small businesses don’t donate huge sums of money to PACs.

Why should Republicans care about startups run by tech bro’s being squashed by big companies? It’s not like they will be able to donate large sums to PACs and they are probably hippy liberals too.