25 years ago, 'customer focus' was the buzz word. Gmail (and similar products) killed it. The internet made it possible for a company to serve hundreds of millions of people without the overhead of listening to, or supporting, or giving much of a shit about them. "Why are you complaining? It's free!" Gmail envy makes it seem like you're some underachieving sucker if you bend over backwards to deliver a great customer…
You're close. It's not Gmail, the product that killed it. It's the business model of "free products." That's because Gmail is not the product - it's a delivery platform that's just useful enough to you to keep using it. The product is ads, and you are not the customer.