Why?

Video streaming consumes dramatically more bandwidth than the HTML/CSS/JS/JPEG/etc files which Cloudflare's CDN is intended to serve. Bandwidth is cheap, especially for Cloudflare, but it's not free. Cloudflare's base pricing, and especially their allowance for free accounts, does not account for such large bandwidth consumption.

Cloudflare does have a product specifically designed to stream video. It is priced accordingly.

Doesn't this conflict with acting as DDOS protection? Anyone can bypass it by requesting a video file?

If I had to guess I'd say it's because it completes with their video streaming service[0].

> Cloudflare Stream is the most affordable and easy-to-use streaming platform.

[0] https://www.cloudflare.com/products/cloudflare-stream/