They pay to be the default, not the only possible search provider.

It was a direct listing at $250 and now the price is $179.

Compared to the S&P 500 which has gained around 75% since then

They pay per click.

Again, they get paid a cut of Google's ad revenue from Safari users. This has one impact on Apple's design choices - Google remains the default search engine.

Notably, this hasn't stopped Apple from introducing multiple anti-tracking technologies into Safari which prevents Google from collecting information from Safari users.

If I open up a new tab in safari it tells me that in the last 30 days Safari prevented 109 trackers from profiling me and that 55% of the sites I use implement trackers. It also tells me that the most blocked tracker is googletagmanager.com across 78 websites