If you're right, clearly Larry/Sergei, elon musk, Steve Wozniak, etc have no place in start ups... I think you picked a controversial statement that's easy to poke holes in
- Google: C++
- Microsoft: assembly
- Apple: assembly
- eBay/PayPal: Java/C++
Like I said, there is simply no room in the early years of a start up to experiment with recent technology. I'd go further and claim that it's actually critical to use older, established technology to get your startup off the ground so you can focus on your idea without being hampered by technological glitches.
Viaweb: lisp. ITA software: lisp.
You've listed people whose stories bear little resemblance to the vast majority of little tech startups that subsist on ramen and go through accelerators.
tldr; hipsters will grossly overestimate their ability to "change the world" with that "brilliant idea" they had this morning in the shower, so starting a new company is pretty much the worst path to take, if you want to "tinker with technology".