Believe it. Firefox is kind of unbeaten in this regard.

There was a study carried out on what kinds of data leaks on browsers during launch [0] but Chromium specifically wasn't measured. I can only infer Safe browsing to be a leak point available on Chromium since it is shipped by default but I have it turned off (never needed it anyway) so I have not observed any pings related to it personally.

[0] https://www.scss.tcd.ie/Doug.Leith/pubs/browser_privacy.pdf