Magic erasers and scrub pads are only abrading the urethane coating on the leather, similar to wetsanding clear coat.

I don't recommend them personally, its a cheap shortcut which compromises the coating on the leather over time.

Use a good interior cleaner that is safe for plastic and not too harsh, something like Optimum Power Clean, usually diluted 3:1 is what I use.

Use a soft bristled brush (horsehair, boars hair, etc) and work the product in the leather with a soft brush to loosen and lift ground in dirt and grime, and let the product work a bit. When done, then wipe the seats down to get rid of the cleaner with a damp towel and let air dry. They should be perfectly clean and matte and you haven't compromise the coating by abrading at the grime on the leather.

Shiny = dirty - my .02 but I don't prefer to wetsand paint if I don't have to and I dont like using abrasives on leather.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards