I am more and more glad I got off the Apple closed ecosystem in 2018. There is so much innovation and variety elsewhere - you can get exactly what you want and it will also be vastly more open for hacking.
I really do hope it's a bug or a mistake. I like macOS but I will never be forced into subscriptions to distribute my own applications. That would mean going back to Linux at home (Beelink mini-PCs seem good for the price), and advocating against using Swift around me.
The closed-garden is good for the iPhone because I use it as an appliance, but a computer will stay a computer for me.
I’ve been using 15.1 since the beta days and the settings panel option to allow an unsigned binary to run has always worked. I see no mention of that option in the article?