It only becomes problematic when you consider that the user is getting themselves into a situation that they do not fully understand and potentially cannot easily back themselves out of.
With drugs that have a high potential to cause harm, we typically force the consumer to consult a professional before allowing them to proceed. Tech is still in the era of patent medicines.
There's no such thing. Email breaks the concept of email security.
LI, Google and Facebook have always wanted your third-party email credentials for Friend Finder-style features. The only difference is that this time we cannot even hope that they delete them after logging in once. Security-wise, it's all the same.
How is that even close to a valid response to someone that's exercising critical thinking?
Access to this many passwords is a threat even if my password is not one of them.
Finally, it may be opt in, but are they going to explain to the user that they get to keep a password for an account to which they have no legitimate right?
I doubt they have a warning when you install this "This is going to let us read all your emails AND the emails of people who communicate with you (without their consent)
...oh yes, and get your username / password for your email accounts"
And if I am communicating with someone who installed this hack then I certainly didn't opt-in.
This is extremely important and getting lost in the noise.