By using an open, interoperable tech stack, you maintain the freedom to switch to another cloud provider at will.
This shared fluid power also creates a compelling reason for cloud providers to remain honest and competitive in their dealings with customers.
For most companies free users are just a source of potential paid customers. Such companies squeeze the free users to force them to upgrade. For Cloudflare the millions of free users strengthen their negotiating power with ISPs around the world. We provide value to Cloudflare just by being Cloudflare customers. It is possible that Cloudflare might get a CEO who doesn't understand this, but possible doesn't mean likely.
In any case, I've built my website with Astro, pulling in the Cloudflare integration as a dependency. If I wanted to switch to Vercel or Netlify or whatever else, Astro makes it easy. As for database, others offer managed Sqlite.
If all else fails, I'll ditch the few dynamic parts of the website and deploy the bulk of the site as static html to Github Pages or something.
Cloudflare offered all of this for free because it gets them positive mentions (like the one you’re reading right now) and they’re educating a bunch of developers on their entire product portfolio. And what does it cost to host my blog that 1000-2000 views a month? Literally nothing.