Personally, I find the whole devops notion a bit bizarre, since, from what I can tell, the theme is one of two.
One is trying to make sysadmins into programmers (or hybrid programmers/sysadmins). This may be the one-way street the blogger is referring to. I could be a programmer if I wanted to, but that's not what brings me joy. There's a reason I've been a sysadmin for my entire career, and it's not some deficiency (i.e. I'm not a layman).
The other is, to my mind, just wishing for better sysadmins. Sadly, I don't think there are enough of us who do know what we're doing, not to the depth you describe. Much of this may be for lack of experience and/or mentorship: they haven't seen it and done it.
when I cut my teeth on sysadmin work in the late 17th century, ops guys drew a line in the sand
This comment was the revealing one to me. Its inference belies long experience. My own start at the profession was in 1988, though, arguably, not in an environment with software developers until '92. Not only did we[1] not put artificial limits on our responsibilities, but I had to fight a couple battles to keep developers from running roughshod over a shared environment made stable through my concerted efforts.
Agreed: We are the league of sysadmins. We know what we are doing.
I would only add: Not all problems are best solved by more code.
[1] originally just me, but then a total of three of us in that environment