We're talking about the value of Phd's to high tech companies, so it's relevant.
Tell me how Facebook, AirBnB, Uber, Microsoft, Salesforce have materially gained from their R&D labs? They would be essentially the same companies without 'research style' R&D. Windows and MS Office do not require PhD's to design, though surely there are material contributions made by those who hold a PhD, but the more classical R&D aspects have not been hugely relevant.
For some silicon companies it's probably true, and possibly in the medical field, wherein clinical research etc. is essential part of the product approach ... but for most of Silicon Valley style companies - it's not.
Companies tend to hire lots of PhDs after they are rich and flush with cash - not the other way around.
"it's reasonable for a personal trainer to get a job as a doctor at a hospital"
No - you need to be a doctor to do 'doctoring'; training to be a doctor is 100% relevant to the practice of actually being a doctor. But you definitely do not need to be a doctor, or even have PhDs on staff to make companies or products that are material relevant to people's wellbeing or fitness.
PhD level, near pure R&D is not essential to the vast majority of even tech startups.
We're on HN, i.e. a Y Combinator site - an entity that is really at the nexus of early stage investment. Care to run down the list of YC investments and see which ones are based on some kind of materially relevant PhD level research - and that are also successful? Because unfortunately there are very few.
I know of one, off hand, Lyrebird - one of the more popularly significant investments that YC has made in AI, they make a really cool product that can take maybe a minute or so of your speech, and then re-create a text-to-voice simulator voice that sounds similar to the pre-recorded device. It's pretty cool, but not that great. It's been a while now, they have no real product that anyone cares about aside from it's novelty, they don't have any real revenue, and they probably won't. Sadly, they will be acquired by some BigCo R&D shop and hopefully make some money for themselves. They are making great contributions to science, but they might as well be doing it out of U. Montreal from whence they came.
Most R&D done by BigCos is just a little more applied than such research done at Universities, but the results of such work benefit the commons as much as they do the companies anyhow. In a way, it's almost benevolent spending on the part of BigCo's, somewhere to park their cash, maintain prestige. It's important in the 'general' context, but often not very directly related to the bottom line of said companies.