Luthier told me to sand my polyurethane neck and it will turn it into a matte neck?

I got a Chinese made Guild D-140 recently. the sound of it! But the neck has a THICK polyurethane finish. For some reason my hands get very sweaty when I play guitar, and the polyurethane neck becomes very sticky and uncomfortable to play. It really sucks.

I called a luthier to ask if there is anything that can be done, and he told me to use 400 grit sandpaper and sand the back of the neck. He said this will effectively turn it into a matte finish. He also said that this will not damage the guitar and will not make it looks scratchy. He said it shouldn’t affect the resale value.

Is this good advice? I would think this would make the neck look scratchy and weird, no? Will this really not affect the resale value?

The guitar is still in the return period, so I’m trying to decide whether to do this or just return it for a guitar with a matte or satin finish on the neck.