That's not true at all.

The bowing out wood underneath makes it look WAY more precarious to the average person. Without some sort of visual out audio cue to signal stress, often people assume that anything that stands without moving and looks intentional is secure.

In summary, if you remove them, unobservant people will lose out on their opportunity to look upon it with fear.

Bylaws of physics

I'm guessing those pretty beefy joists are cantilevered, and the 2x2s are unnecessary. They were likely added for the joke.

Might not be that long, they could have easily had it all lying around. They don't seem like the type to go out and buy new lumber just because.

The wood looks weathered, but not rotten. And the joist on the front is probably the most weathered, since it is the most exposed to sun and rain, while the others have been protected by the roof.

I'd argue for a thorough inspection, and my bet is that most of the joists would be in pretty decent shape. Replace the ones that need replacing, and then sand and stain for better weather resistance in the future. Would probably be a project that takes a couple weekends for a competent DIY-er.

Hi, did they replace them? Was it a mistake?