Be careful with point 2, "Let’s not even talk about job-security".
I know, I know, the startup ecosystem (more specifically, web startups, so I suppose the term engineer refers to that too) are booming right now and nobody can imagine how bad things could ever happen. Yet, often enough, bad and unforeseen things do happen, a boom ends rapidly, lots of people are without jobs. Don't scold the guy for wanting to know where he will be at in a couple of years.
The point the author makes under that heading is: One need not worry about job security at a specific startup, because if it goes bust one can always join another startup.
Except when they "all" go bust. There is only so much VC money to go around and when that contracts open positions do too. We've been in a good period for a while but tech is also very cyclical.
I know, I know, the startup ecosystem (more specifically, web startups, so I suppose the term engineer refers to that too) are booming right now and nobody can imagine how bad things could ever happen. Yet, often enough, bad and unforeseen things do happen, a boom ends rapidly, lots of people are without jobs. Don't scold the guy for wanting to know where he will be at in a couple of years.