No i am pretty sure it is not mean't to be funny, it is genuine, comes from a cat site, but i cannot be 100 per cent sure, but i sure can relate to all of those tail expressions, Lexie's tail quivers when i pat her, like she is spraying, but i knew she wasn't,but often wondered why she does that, she is the only cat that does, now i know, we live and learn, nice to know a few more things about our kitties.
When Nikki hears another cat outside, she runs upstairs, hoping to get out, NOT HAPPENING, and her tail can get bushy, but is in the downward pose, i have seen it straight up, when approaching another kitty on our property, so i would say these are genuine.

I found it very interesting and had to share.