This is one of those suggestions that are so obvious one has to wonder why it hasn’t been done before. As you detail later in the article, Apple is aware of the problem and has put in place certain considerations (screentime, airplane mode) but has actively avoided others. My theory is that design is something Apple is unwilling to compromise on and allowing users control over the look and coloration of their notifications is “compromising the design” in Apple’s book. I’m with you though, we should have flexibility and control over our own phones… we certainly pay enough for it.