Sorry, that's not even close to being true.
Interesting how on HN "hardware" seems to mean "a board with chips". You know, like a Raspberri Pi. That is one type of hardware but not, I dare say, where the $10B (and maybe even $10M) startups would exist.
We are developing two hardware products right now. One is an innovative fire fighting system and the other a CNC machine. The complexity in these designs has very little to do with what chips you place on a board. For example, we expect to have to run three to six months of FEA simulations to validate aspects of the fire fighting system and then have to iterate through several design candidates over several months.
Beyond that there are regulatory issues that could up-end any design if you don't know what you are doing.
Packaging. I almost forgot packaging. Man, that can consume months of testing. You can design a beautiful product only to have it damaged during transportation due to incorrect packaging.
Oh, yeah, you also have to have good software.
Nah, harware isn't just about chips on a board.