Yeah, that stickyness is called rubber reversion. Every device with that soft touch rubber coating will eventually do it. It comes off easily with alcohol. With a little effort you can clean it off and have a perfectly fine plastic mouse without the rubber texture or stickiness.

I have many old devices still in use that just stripped off the coating when it went bad.

I’ve got a “808 Hex” speaker I bought on a whim almost 10 years ago that is incredible. It is Bluetooth or line in, has a barrel jack DC wall wart, or it takes 8 AA batteries. I use rechargeable AAs. Its less convenient to charge than speakers with integrated batteries, but it will likely last forever because it doesn’t have one.