IANAL either, but yeah, the practice you're describing, using revenues from other parts of a business to subsidize the areas it wants to compete hard in until the competitors are dead, is typically known as "predatory pricing", which is illegal. IIRC, Standard Oil was a big user of that playbook.

I don't know if this qualifies, and I don't know how much appetite there is for prosecuting Google for offering useful things for free. I don't think they've had much of a history of jacking up prices after killing off a market, until relatively recently. Interesting question, though.