I'm actually going to defend some of the most popular pokemon posted on this thread:
trubbish/garbodor: I may accept the fact that you don't like the design, but insulting the idea behind it is not okay. There have been some slime pokemon in the past, such as muk and swalot, and considering the pollution levels in the world, one might say that one of these slimes actually adapted to the garbage, producing a living creature whose life depends on another object, which exists in the real world. Plus trubbish is just adorable
Stunfish is based on an actual fish, I'm not sure if it's the flounder or the dab, but if you find its design derpy, blame nature
The other ones i don't know how to defend, especially jynx