> they use jump cuts to mask recording mistakes or to cut out pauses

Both of which of course have a lot to do with reduced attention span.

Pauses and mistakes objectively add negative value to videos it's a good thing that it's removed.

Showing a well placed recording mistake shows the youtubers is still human. You see it all the time in videos and of course it's on purpose.

I need to be in a certain mood to care about the video's "humanity", rather typically I just want the information.

> they use the jump cuts to mask recording mistakes or to cut out pauses.

Over time, it becomes a culture signifier of sorts. MrBeast is bigger than Pewdiepie (embarrassed that I know these names), he obviously does not need to paper over mistakes with those cuts.

Same way he doesn't need to make exaggerated open-mouth face for the Youtube thumbnail, but they do anyway.

There have been a few people that examined the topic of YouTube thumbnails, even with a/b testing and statistical analysis (since YouTube allows you to change it and gives good stats). It really does matter to getting views.