I kinda like the sticky rubber, since I mostly ride without gloves and it provides good grip.
Seems I just have to live with it, since Shimano warranty terms state
https://bike.shimano.com/en-US/informat ... ranty.html :
Disappointed by Shimano reg. the durability of this surface coating.THIS WARRANTY DOES NOT COVER THE FOLLOWING:
[...]
5. Damage or deterioration to the surface finish, aesthetics or appearance of the product.