I totally agree with what you said. We need more personalized education systems. But this article is a red herring. If you actually read the data and figures from the article, the conclusions have been twisted to create clickbait. In particular, the article talks about persistent INSTABILITY of sleeping schedules. "We quantified SJL as the difference between the average phase of activity on class days and non-class days." This has nothing to do with the disadvantage of night owls to non-night owls, but rather talks about the disadvantage of folks who oscillate their sleeping schedule from day to day. It doesn't matter if you're a night owl or not, that's going to kill anyone's productivity. The audience read what they wanted to read, and interpreted this as "night owls vs. early birds".

here's the original article for reference: https://www.nature.com/articles/s41598-018-23044-8