As usual this started with an incoming phone call. If you ever receive a phone call from a tech company, it's a scam. The caller ID doesn't matter. The caller's accent (wtf) doesn't matter either. It's a scam.
If the consequences for letting that call go to voicemail are any less severe than full account takeover by a script kiddie, you're still better off never picking up.
Google in particular is famous for making it impossible to contact a human. If Google calls you, before picking up, consider whether you truly believe you're lucky enough to be one of a handful of people in the world to ever get human support from them.
I've spoken on the phone with humans in Google support. (You, too, can do this, just pay them enough.) However, they called me after I filed a support case and specifically requested a call, and they started off by mentioning the number of the case I had filed.
If you ever get a cold call from "Google Support", it's basically guaranteed to be a scam.
After I got Google Glass in 2013 as one of 8,000 "Explorers" I was given a support telephone number that was always quickly answered by a Google employee knowledgeable about Glass.
You still always assume an incoming call is a scam no matter what. Hang up, look up, call back, in that order.
Very occasionally you might be making some poor customer support person's job harder, but the vast majority of the time you'll be hanging up on a scammer. You can be polite about it, but firm and brief. "It's my policy to always call back no matter what, nothing personal."
The problem is verifying which number is correct. In most cases it's pretty easy. Bank? Call the number on a debit card. Google? Good luck even finding their number.
But I do agree with you. They can leave a message and a way to contact back if its important and I can take my time doing research. The urgency part is what's caught so many high profile people off guard.
Low-margin businesses always have bad support, and there's nothing you can do about it.
High-margin businesses usually have passable or good support. If your vendor of choice does not, you have chosen the wrong vendor and should switch. There are other options that do a better job.
I do this for any inbound call, unless the caller id is someone in my contacts it can go to voicemail. If it's important they either leave a voicemail or keep trying, for repeated calls I will answer but with skepticism.
If they are in my contacts I will recognise their voice.
I regularly get phone calls from Google because I helped a friend with their ad account once. No matter how many times I tell them not to call they eventually find a new number to call me from. They are legit calls. Google just won't take no for an answer.