I personally use Safari on all my iDevices and macOS. It has much better integration with Apple's OSes, that's essentially it.
In iOS, the browsing engine of every single browser is safari (webkit, I believe), the only difference is the "wrapper". If the browsing engine is the same I rather not give my data to google.
Also, I like that safari is less in your face and just nicer overall to use. as well as using the the hand-off feature when browsing from one device and continuing in the other (nice popup shows up).
iOS has the ad-blocker settings for safari, not sure if those apply to chrome when set.
On Mac I switch back and forth between safari and chrome, but I try to stick to safari because power management is much better and it integrates really well with the Touch Bar for video playback and the like (also I can natively start the picture in picture feature in almost any video, even youtube).