Habitual use of shorter and shorter form content trains you to expect gratification faster and faster. There is most certainly a better reward for delaying gratification. A really good movie can leave you on a complete high or completely devastated. I'm pretty certain tiktok cannot. It's cheap quick entertainment but if you get used to that fast shallow enjoyment you can't hold on long enough for the good stuff.
I understand. The same arguments have been with us for a long time. See Conrad Gessner's arguments against the printing press.
Since rolling back to at least the pre-radio days is unlikely, we might focus on educating consumers in a way that empowers them rather taking a top-down approach to control what people are allowed to do because we know what is best for everyone.