Waterproof mattres pad on latex mattress

Hi Phoenix - I’m planning to put an Allerease Organic Cotton Top waterproof mattress pad on our guest bed, which is latex. This just happens to be the mattress pad I have. My only concern is whether the waterproof part of it (I think it’s polyurethane) will be bad for the mattress because it could restrict airflow. It’s my understanding that latex needs to breathe in order to not become a host for mold (which is why it’s not recommended that they be placed on the floor, right?). So will having the top layer effectively sealed in with a layer of waterproofing material have the same effect? I looked at the Luna and Protect-A-Bed Luxury that you spoke about in another post (as being popular options), but I’d rather not spend that much money - UNLESS, of course, it will make a difference for the longevity of the mattress! Then I will replace my Allerease.

And just to be clear, I’m not really concerned about comfort or flexibility - I just want to protect our mattress!