With COVID still around some mainboard manufacturers probably Hough it would be a good idea to re-introduce washable keyboards. 

Kensington releases the "Pro Fit Washable Keyboard," which allows you to easily wash the entire surface . It is suitable for use in places where the keyboard is shared by an unspecified number of users, such as medical institutions, schools, and internet cafes.  Using a waterproof design that covers the precision equipment inside the keyboard with a thin film. It also has a drainage mechanism, making it a safe structure for spilling liquid. It is also resistant to washing by immersion in water, and can be washed in whole using a non-abrasive detergent, multipurpose detergent, soap, germicidal disinfectant, bleach, rubbing alcohol, etc.

The keyboard layout uses a Japanese layout, giving it a soft-touch feel. The connection interface is USB, and a PS/2 conversion adapter is included. The external dimensions are width 445mm, depth 170mm, height 25mm, weight 580g.

The more I think about it in these times, not a bad idea at all really.

Kensington releases "Pro Fit washable keyboard", can be washed with water and detergent