I have no idea how you came to this conclusion. It's obvious that I'm criticising the idea of "sideloading" not the word. You can call it some other arrangement of letters and the concept is still very dangerous.
And in this case it is also definitely true that apple does not let you install applications without someone paying them $100+ and their continued approval. The "let" is the key here.
The way I came to that conclusion is I read what you wrote, which primarily discusses the language, not the idea. See your references to “doublespeak”, “framing”, “headlines”, and “the word sideloading”.
You claimed “Installing applications on iOS 17 might be allowed in Europe” would be a more accurate headline. It wouldn’t be, because you can install applications via the App Store. If you wanted your headline to be both accurate and to discuss the approval process and fee, you would need to include that, as the original headline does by mentioning “sideloading”, the word that you take issue with but does at least actually raise the issue you’re concerned with.