The eventual removal of that tier and anything even close speaks to Google's general issues with cancelling services, but that doesn't mean it was less real while it existed.
I don't remember the "increasing forever" ever being particularly fast. I found some results from 2007 and 2012 both saying it was 4 bytes per second, <130MB per year.
So it's true that the number hasn't increased in ten years, but that last increase was +5GB all by itself. They've done a reasonable job of keeping up.
Arguably they should have kept adding a gigabyte each year, based on the intermittent boosts they were giving, but by that metric they're only about 5GB behind.