How much gets thru the Canton depends on the media's micron rating. The typical Canton media cartridge is 8 micron. That's pretty good
https://www.cantonracingproducts.com/cgi-bin/commerce.cgi?search=action&category=2500
However it's also important to recognize how many GPM the filter can flow. That's always been my concern with the small Canton that can fit on the filter housing on the engine case (the one that replaces the oil cooler). Is 12 GPM enough? I don't know that answer.
https://www.cantonracingproducts.com/product/25-184/25-184---CM-34quot-BILLET-SPIN-ON-FILTER-20MM-THREAD-2-58-O-RING/
The OEM style disposable can filters typically have a rather low bypass valve pressure rating, do they not? For instance the Mann 940-29 filter for a '78 to '94 911 scavenge filter (equivalent to Mahle OC-54 or OEM filter) has a bypass valve cracking pressure of 2.5 bar = 37 psi. I don't know how that translates to actual engine oil pressure. But it would seem that at high rpms the OEM filter enters bypass mode and a good amount of oil is therefore bypassing the filter?