Cloudflare can collect your traffic history, but can only connect that history to your originating IP + timestamp. Their official client may be able to collect more info though. But, warp is just wireguard, so you do not need to run their official client there are shell/python scripts floating around to get the keys / endpoint IPs setup for Warp to use with std. in-kernel wireguard.

Further, all the telcos in the US are known to have colluded in illegal NSA spying on Americans. Cloudflare has not been caught at this yet. So, you can look at it as a choice of exposing your browsing history to an entity that may be not be lying and actually is not snooping vs. telcos that are known to have lied and definitely have and are likely still snooping.