Can I use IVS with CDN removed?

Amazon IVS uses its own CDN based off of Twitch, and you cannot remove it. As the docs indicate, it is highly optimized for low-latency.

https://docs.aws.amazon.com/ivs/latest/userguide/security-resilience.html

Video ingestion and distribution run over Amazon IVS’s Content Delivery Network (CDN). The CDN is specialized and highly tuned for low-latency video. This enables Amazon IVS to provide customers with end-to-end, high quality video served to a global audience with minimal delay.