I'm not sure I would count defense contractors as "tech companies". They're a different category, even if it involves technology. (If tech includes Defense, then why not also Automotive? Or financial, medical... What isn't tech at that point?)
I mean, depends on the company, the one I worked for was solely all software for example, they took a Linux distribution and made a custom distro to be installed on whatever hardware the client chose, it was very niche and single purpose. This was our primary product, our only other alternatives were all software as well. I would highly count that as a tech company.
It's pretty broad these days. Reminds me of Uber, a ride hailing company, aka taxi service. How much of the company needs to be tech vs the service? Like Bell Labs and AT&T?
The lines are either far too broad or far too fuzzy, indeed. Why is Netflix tech and not Disney? Tesla but not Ford? Amazon but not Walmart, Apple but not Dell, or Robinhood but not UBS?
Hell if I know, but I know there's a line there in my mind.
In the case of Craigslist would you call it ecommerce? Probably not, they facilitate contact between buyer and seller, they do not process payments, its not like ebay or Amazon, Uber is a fancy Craigslist.
