Facebook requested, even occasionally demanded, mobile phone numbers
from its useds in the name of "security",
then treated
them as personal identifiers for lookups and advertising.
Since two-factor authentication requires a Stalin's Dream device, I am
excluded from all digital services which demand two-factor
authentication. MIT administrative services do this, so I cannot talk
with them on line.
In September MIT demanded that I take an online course about sexual
harassment; although I don't teach classes or even meet
undergraduates, they treated me like a professor on the "be
overcautious at every opportunity" principle. But I was unable to do
so until MIT arranged to let me log in on an MIT kiosk terminal and
bypassed the two-factor requirement for me.