"That's not the phone number associated with my internet account -- that's my mobile; you want the landline. Yes, I'm calling from my mobile... because the landline doesn't work. It doesn't work because it's VOIP and the internet -- which YOU provide -- is down. And even when it DOES work, it goes right to voicemail to stop the spammers, so don't expect me to receive a callback there."
The former half of the above exchange has happened at least once at a former residence.
The latter half relates to the article in that one of my wife's financially related accounts had only said landline for contact and tried to call it with a one-time login code (wouldn't do email, too convenient as she was only in the next room with her phone w/ email clients). I had to open another browser tab, log in to the VOIP, turn Do Not Disturb off, test that I could even get a call on the emergency phone, then attempt the original login. Then get another OTP when I attempted to add one of our mobiles as an alternate number, more OTPs to verify that phone, the set it to primary as soon as I could (I may have even deleted the original), then put the VOIP (and everything else) back to "normal".
Trying to keep oneself secure and unbothered is itself quite a bother when they NEED to contact you, using the worst possible method, for the sake of said "security" (whose -- mine or theirs?).