No.
We haven't used CloudFlare for caching (aka "reverse proxy" or "CDN") in years. We tried it several years ago, but found it too problematic for our users.
As of now, the only service CloudFlare currently provides for us is DNS. We continued to use CloudFlare for DNS due to the flexibility it provided us to switch servers at almost the drop of a hat (we could easily switch caching on and off if need be).
DNS was not affected, only the caching side.