Why? The price you're actually going to pay is what matters. Though even if you insist on MSRP for some reason, the DualSense is $75 and the Xbox controller is $65, and you can get these for $25 MSRP ($18 actual) for two, making the Xbox controller barely more expensive if you have an even number of them.
If you compare the prices today, the Xbox controller is $50 compared to its $65 MSRP and the DualSense is $74 with a $75 MSRP, so you can get two battery packs and a controller and still pay $68, $6 less.