That magnet is blocking 1/7th of your oil going into the filter. That’s a horrible place for a magnet and I’d stop sticking it there. That’s about a 14% reduction of flow of dirty oil to the filter. The filter can be a pretty big restriction in the system anyway and you’ve just caused a flow reduction for no reason.
If you are interested you can hook an oil pressure gauge up before the filter and another one after the filter and read the difference between the two. That difference is the pressure drop across the filter. The higher the difference in pressure, the more restrictive the filter is.
That said, if you are getting that much junk every time on the magnet, I’d be keeping an eye on anything cam related. And I’d get rid of the magnet and just cut the filter open. Or use a magnet like mentioned above and still cut the filter open.
