I'm 35 and I can already feel this happening. There just isn't much of a career path if you don't go into management or own a business. Maybe at the huge companies (Apple, FB, etc), but not most, and definitely not in most geographies.
What I don't understand is why it's different in tech vs. other fields. Maybe because they're professionalized and can't be cut out? Whereas tech is more capitalistic overall and reinvents itself every 5-10 years in a way most other professions couldn't imagine? Not sure.
"Free pizza and snacks" does feel pretty infantilizing. Heading into my late 30s, I'm not game for that anymore. It's not even just the money, it's the overall approach to work, the open-plan offices, having little autonomy, little networking or visibility into the business, routinely having my judgment overruled by the latest VC-backed 22-year-old, dealing with stupid and avoidable tech debt, death marches, and cleaning up others' messes. After three failed startups, it's gotten tiresome to the point that I've decided not to work in those companies anymore, and really given a hard think to my personal career plans. Even as the executives of these bankrupt businesses have all failed upward into senior director roles at larger companies and sama and co. continue to preach the gospel of fast wealth and career growth at the latest darling run by "geniuses" 3 months out of YC.