alt Hacker NewsIt probably makes things easier, but its unlikely that the industry that found a way to make foldables waterproof couldn't figure out a way to put rubber gaskets on battery covers. And in fact, they did, there were several devices introduced in the transition period that had both features.
Rubber gaskets wear out. Best practice is to replace them every time you open the cover. We can put them in, but the replacement battery better come with the gasket because you can't safely replace the battery without a new gasket.