Regarding email validation, ICANN has made possible to create top-level domains, making the length limitation of 6 obsolete, as can be seen on this list.
Coverage remained the same at 99.462% when pulling 8ec5ba65a0103c89fd0c35e96ad2929cf2f67f56 on AlanVenegas:email_regex into 89b3b2304e2d5ede0631079f485c8aa97e3eacfe on jonasschmidt:master.
Regarding email validation, ICANN has made possible to create top-level domains, making the length limitation of 6 obsolete, as can be seen on this list.