Fines are often gamed: lobbying, legal defence.

I would argue big companies care more about losing customers. Сompetitive pressure is more effective than laws and fines. And laws are not without downsides, including becoming barriers to entry into competition.

Billion ain't much nowadays. The big 5 do 100B+/year in net profits. <1% doesn't matter. It's like being fined a $1000, while earning 6 figures. It feels like a pinch.