Idk why caller ID spoofing is still a thing that carriers just let happen.

Email has had the same problem and we have since built solutions like DKIM to more or less get rid of most spoofing attempts.

I have a "business" VOIP account and I can just populate the "from" number with anything. My asterisk box is considered like a small carrier and my carrier will trust it. I think I could also announce numbers I do not own to get incoming traffic but I never tried. I use the caller it for redirection, when I call out from my fixed line, my mobile number is displayed, so people call me back on mobile.

Not to shame the author--I'm glad when people share the stories--but the thing that surprised me is that the author knew the "hang up and call the number on your card" advice but didn't seem to understand why it's common advice. The whole point is precisely that caller ID is completely unreliable. If caller ID were secure and authenticated the caller, there'd be no need to hang up.

Seriously, this is even more embarrassing than the nearly-identical blog post that was on here a few weeks ago.

Depends on the country in the US its relatively common. Other countries it can be much more difficult.