The war of the Five Titans now is one over where to dig moats and lay down drawbridges, and ticket-booths. Google. Apple. Amazon. Facebook. Microsoft.
MS is still, mostly, based on preloads and sales, though it's shifting to subscriptions + ads.
Google is straight-up advertising.
Apple refutes that hardware is a commodity.
Amazon sells ... everything else.
Facebook is Google, but weaker: Advertising without intentionality. (But it's bigly useful for tyrants and puppets.)