Just one study but we have seen clear decreases in human attention spans, esp since 2012...
"Watching fragmented short videos rather than a single continuous video leads to poorer memory recall and alters how the brain retrieves information. A recent experiment revealed that fast-paced episodic media formats disrupt the neural systems responsible for integrating details and maintaining cognitive control." via PsyPost

Brain scans shed light on how short videos impair memory and alter neural pathways
A recent brain imaging experiment reveals that watching fragmented short videos leads to measurably worse memory recall compared to viewing continuous content. The fast-paced format reduces brain activity in regions dedicated to focusing attention and processing deep meaning.
