Why do magnetic oil drain plugs come with copper washers?

[JStryker]

Just wondering why they come with copper and if it matters if the next oil change you replace the copper with a regular steel washer.

This is the item:

DEEFILL Oil Drain Plug M12 x 1.25, Magnetic Oil Pan Drain Plug T6 Aviation Aluminum with Red Copper Crush Washer Gaskets Compatible with Toyota, Lexus, Nissan, Infiniti https://a.co/d/15Unvsh

On another note does anyone have any bad/good notes about their experiences with magnetic drain plugs or is it more of a gimmick?

Lastly does anyone use a tool/specific wrench to remove the old oil filter? I was thinking on getting the giant grip pliers for removing oil filters but liked the cup/socket combo. I just couldn't find one that was for a Yaris 90915-yzzf2 filter.

Thanks I'm advance