True, those bugs are worrying. But I still feel iOS and macOS are the most secure choice because:
1. This incredibly obscure bug (in the sense that I'm surprised someone was able to find this) was found relatively quickly
2. After it was found a fix was developed and tested quickly
3. Once that fix passed QA my devices received a software update over the air and the problem was solved. One of the big problem with other mobile OSs is that the OS updates are often going through the carrier or device manufacturer and it takes time or you don't get it at all.
I don't expect a device that's perfectly secure. I'm sure there are hundreds if not thousands of undiscovered vulnerabilities on the device I'm using to type this to you right now. But that's not the whole picture on security.
There are blunders - but the difference is that there is a lot of scrutiny on iOS and macOS compared to other more niche options. But I guess security through obscurity is not too bad. Apple did benefit from it for many years.
Indeed they have. Apple also agreed there is a problem, and they are apparently trying to fix it. Better answer to the problem than I expected, honestly.
Remembering that macOS bug with empty password root access, I'd say that Apple security QC had degraded a lot.