They will definitely get slippery eventually, but it might take some time for yours, depending on how much you use your keyboard.
I do really like the texture of PBT keycaps, but some of them feel better than others. I have Cherry profile PBT caps right now, and they feel just like the PBT keycaps on my Cherry G80-3000. Very smooth, but still texturized. Good ABS keycaps can feel good too, but that's keycaps like GMK or SP doubleshot ABS.
I also find that PBT keycaps feel kind of bad on clicky switches, they seem to make the click feel less "crisp". PBT keycaps do feel nice on tactile and linear switches though.