There really is nobody left who could possibly give a hoot about the contents of my email box. But I think I'll still add a codicil to my will that said contents (as well as my hard drive) should just be allowed to vanish into thin air.
In my will I've specified that not only should none of my email accounts be accessed under any circumstance, but that all my computers should be dismantled and the hard drive destroyed. I also made a point several years ago of informing anyone who may need to deal with my effects that this should be done immediately, and that there is nothing on my computers that anyone need examine after my death.
I also have some rather harsh stipulations for anyone who fails to follow my instructions in this regard. In short, they will get cut out completely unless there's a legal order that prevents them enacting my wishes. I thought about all the possibilities many years ago, and I think I've covered all my bases.