In the earlier days it was like that but as time went on it became a technique known as sweetening to make the joke seem funnier, sometimes they would even use it to fill in silence or dead air since that was frowned upon (I wonder why people said TV rots your brain for the longest time... can't be related to any of these practices could it?).

The beginning part is essentially saying that if people need laugh-tracks to find things funny they are dry and humor-less, a joke at their expense but also at the same time it's 100% sincere, a person who can't find things funny without others lacks a sense of humor.