Alumni email addresses are sometimes filterable, due to a different domain, but faculty or staff generally aren't; at many schools, students, faculty, and staff

Alumni email addresses are sometimes filterable, due to a different domain, but faculty or staff generally aren't; at many schools, students, faculty, and staff get indistinguishable email addresses. I considered trying to sign up as an alum to test it out, but decided that I don't really have any interest in chatting with random Ivy League undergrads even if just for testing purposes.