Perhaps the new leather did not come with the urethane clearcoat? I'll see how it looks when I pick it up today. If it doesn't look close enough, I'll see if I can get the leather coated.

It did come with the urethane clearcoat - leather does NOT come shiny from the factory

I understand. This is what my seats look like. The new seat is flat/dull compared to this.

Maybe it was old stock and faded over time?

Got her home. Seat looks better after they put some "treatment" on it. I'm sure it will look better after it's gotten some use and a little "patina" on it. Here's the new passenger seat and the existing driver's seat.

Curious what your rear seats look like. My rear seats have essentially never been used and the black leather is completely flat with no sheen. No shine at all. Almost looks like a different type of leather than the front seats. I did not realize until recently the shine on my front seats was actually filthy oil and grime that has layered up over time.

Looking at your comparison photos, I can see why you might be concerned. However, I would try to thoroughly clean your drivers seat with some high quality auto leather cleaner using a cleaning brush to remove all of the deposits, then do another comparison. And, of course, after the driver's seat is totally clean I would not put any 'shiny' stuff on it until after the comparison.

Again, your driver's seat is not supposed to be shiny, even if you put shiny stuff on it. It is supposed to be flat. For example, if I put shiny stuff on my rear seats I barely notice a change. They remain flat because they are so clean.

Use a Mr. Clean Magic eraser on you driver seat and you will get that dull look like the new passenger seat bottom.

That is a huge difference! I think you'll have to try to shine up one and dull the other to try and meet in between somewhere.

Thanks for the suggestions. I'll try cleaning the seats and see if they dull up a bit.

The Magic Eraser won't harm the coating on the leather?

Check out the YouTube video "How to clean your leather seats with Swissvax Leather Cleaner - by Auto Obsessed" for an example of shiny seats that should not really be shiny.