I'm confused as the point of this video. Is it to defend lackluster, average movies against some marginal class of people that hate said movies? I ask because, per the consensus, Waterworld is an average to slightly-below-average film. 46% on Rotten Tomatoes, 5.9 on IMBD, and a 56 on Metacritic. It's pretty much on the review spectrum where a popcorn, 90's-action film would be. Who are you defending this mediocre movie against?
You are also doing a disservice to the films detractors (not haters) by not addressing any of the faults and straight out misrepresenting the movie as "doing nothing wrong." It's overly long, the protagonist is unlikable for the first 90 minutes, the female lead has zero personality other than "protect my daughter, i'll show you my tits if do!," things in the movie make no damn sense (though you did bring up dirt, but you left out the oil should have run out long ago and the cause of Costner's mutation is never adequately explained), and all-in-all, its just an average action movie that reached way too high and had an anti-climatic ending. Most action movies of the 90's didn't hit $150 million domestic in the box office (case in point: True Lies, which came out the year before with a much better action star and female lead and a had far superior director in James Cameron, only earned roughly $146 million) but the studio signed on to make one that cost $175 million (not counting advertising) anyway. Hell, Waterworld made almost $10 million more than the superior and a lot more fun, popcorn-action-flick Demolition Man.
How about you defend bad movies that almost no one likes? You can start with any on this list:
http://www.imdb.com/chart/bottom