Is it really true that ignorance is bliss?

It seems that many people live happily being blissfully ignorant. I was thinking that someone who is blissfully ignorant may not worry as much as others. But at the same time it might be trouble to be blissfully ignorant. I was watching Sadh-guru speak about this. He said that ignorance is bliss until life knocks you in the head. He gave an example: Go to the highest building and be ignorant of gravity. Just jump. It will be so blissful for a while, but that is only until you smash into the ground.

While ignorance can be blissful, it is barely a solution to life. Life may knock you hard on the head if you’re ignorant of basic things. What do you say? Do you know anyone who is blissfully ignorant, and is that working for them?