Accepted cryptography is also security through obscurity. The thing is that the amount of obscurity must be quantified. Cryptanalysis allows one to calculate these quantities of "obscurity." Then, a full study of effectiveness combines that with the costs associated with brute-forcing the bounds arrived at by the cryptanalysis.

Other parts of infosec are the same, but often with less well-quantified measures of effectiveness. E.g. memory hardening techniques like FORTIFY_SOURCE and MTE are effective in raising the difficulty of exploiting memory vulnerabilities, but under some conditions the vulnerabilities may still be exploitable.

Before using labels like "security through obscurity" one has to first answer: how much does the technique raise the cost for attackers? This is what articles about security systems (including this one) should focus on. In the end, hacking, like most things, comes down to economics.