It is designed to, though. That's the thing. The line is arbitrarily drawn at not getting CLI/root access to your iPad.
His point is that over the years, Apple has blurred that line a lot. You can use keyboards and mice. You can do all your daily computing on an iPad - email, spreadsheets, YouTube, whatever.
But it's still locked down, for whatever reason, despite being a perfectly capable computer that doesn't necessarily need to be.
It's honestly really obvious what he's saying. iPads have changed over the last 5 or so years, and people on HN clearly haven't used one in a while. The author isn't _wrong_.
Apple spends all this effort to blur the lines between personal computer and a device you can compute on, and it mildly tricks users who don't necessarily realise there's a difference between the computer and the tablet, especially amongst younger generations who grew up on tablets ("iPad kids").