From the page:
Avoid stacking everything on a single vendor when it really matters (DNS + CDN + WAF + hosting all in one basket).
I'm not sure I understand several of the statements in this article, such as the above. If my entire service is built on Cloudflare (Workers, DNS, CDN, WAF), moving my DNS to GoDaddy doesn't improve my site's reliability. The only way I'd improve reliability is by having full redundancy of each component, end to end. In other words, a region or availability zone.
There's an industry gap for good alternatives to Cloudflare, but they already make so little money for the value they're providing, why bother?