Blockchair is one of the longest standing one with a clear privacy policy that respects your privacy: https://blockchair.com/privacy. However, there is no way at all to prove that they don't collect any information, and thus you should always assume that your privacy is compromised when you're using a third party service.

An easier way for your privacy to be compromised is to use ISP, or perhaps even VPNs/Proxy. They don't exactly preserve your privacy and it the traffic is easy to analyze by an intermediary. Using Tor would be advisable to mitigate this, and with the rotating identity, you can probably preserve your privacy better with the onion service anyways.