They are cutting out the standing around between each play in which the clock runs. That's all.
That's not all that happens during that time, though.
Substitutions happen, and sometimes the offense tries to hurry and snap if they see the defense screwed up... or you see a guy didn't get off the field so one team had too many men on the field.
IF you cut all of that out, then some stuff needs explanation to know what happened.
I'm not a fan of cutting down beyond the actual gameplay time in football. Cutting down below the 60 minutes of clock running is cutting out stuff I might want to see... so I haven't watched any of those cut-downs that air on the NFL Network either.
In basketball you have another problem to contend with... Yes, there are only 48 minutes of timed play... but the clock does stop on out-of-bounds plays (non-scoring ones) so IF you cut out those plays you wouldn't see what happens during an in-bounds play... Fouls and turnovers and other stuff happens with the clock stopped. Also, free throws occur with the clock stopped. Cutting that stuff out would cut out some important things.
Imagine if soccer was cut down to only the actual scoring play... most of the time it is setting up for a scoring play... so in a 90+ minute soccer game, you would cut to what 5 minutes of gameplay if you cut out what was deemed "not necessary"?
I do agree that commercial timeouts have gotten longer... and more of them over the years... and the Super Bowl halftime "extravaganza" has gotten out of hand. College sports has longer halftimes too in the tourney/playoffs/bowl games.