It was there originally. I didn't feel that the second sentence did much to affect the overall thrust of the post ("not necessarily" isn't exactly very generous), and even if it did, it's still quite possible to disagree with the notion that having moved out and achieved financial independence by 21 is a requirement for "not a failure" status.

I feel it's exemplary of an arrogance and myopia many of us programmers are possessed with. Our profession is undoubtedly high-impact, but it doesn't actually require all that much knowledge to be useful at it, nor is it that difficult or time-intensive to learn. It's relatively easy to be successful at it and make money even at a young age. Many other paths are much more difficult, take a lot longer, and are no less worthy. Ones that require much more knowledge, or experience and personal growth, for example.

If you try really hard you can chose to read that parenthesis as a passionate plea for society to recognize this and support them better, I suppose, but I'm not that optimistic.