Yes I agree that is isn't specifically about TV. It's about the power of peer pressure and the behavior of crowds. It's known that people try to align themselves with whatever they believe is "the norm" in any situation, even if this contradicts their prior beliefs.
First, the two studies are more than 25 years apart. Society has changed, and so have we.
Second while participants believed they we "on a tv show" it's a logical leap to believe that this would somehow be a extenuating factor than if they were at a gathering of some other sort.
A 15% jump, to me, would show that the variable of the "TV" played a part.
I also think it's a leap to say television caused this. If they really wanted to prove causation, they could have tested it back to back in different regions. Instead, they settled on the answer they appeared to be looking for all along, that it's just TV.
The variable was mostly just "large live audience egging the participant on".
If the participant were able to reason under contrary social pressure, he'd probably consider that the general (much larger) TV audience wouldn't necessarily react in the same way as the taping crowd, which is generally known to be prompted.