Looking back over the past 3-ish decades, becoming utterly dominant in some part of "essential" stuff on the internet has a way of paying off big.

Or, they discuss their free stuff at length here - https://www.sec.gov/Archives/edgar/data/1477333/000147733326....

(That is Cloudflare's 10-K for calendar 2025 - scrutinized by serious investors, and with heavy penalties for lying.)