When you need a big tank

https://www.youtube.com/watch?v=alUCqLzB7vs&ab_channel=NipponTVNews24Japan

Fish will die even in a big tank.
There are salt and fresh water species that should not be kept in aquariums of any size.

I suspect Willie was joking with us. However, we all should realize we may not have proper tank for fish we like and/ or some species will not survive in the tanks we have available.