I have a friend that never played pokemon before I presented it to him and never liked the anime (he was a digimon kid).

He say he can't see the difference between the new and the old pokemon. He give me the example of scyther, venusaur and rhyhorn that are very detailed pokemon while cherim and rotom are such simple ones. There are simple and overdesign ones in every generations. He prefer the new ones because they're based on specific animals or legends while most of the old are just monsters with some exceptions.

My cousin on other hand, that also never played/watched pokemon before me, say that the main difference between the new and the old is that the new are more extreme. If a pokemon is cute, it is very cute, has a big head, big eyes, looks like a puppy; On other hand if a pokemon is ferocious, it looks very dangerous, it has spikes, teeth, claws and a lot of points and ponty marks. Garchomp is the extremo os this, everything on his appearance says "danger".

That's 2 no-nostalgia opinions. Take your own conclusions.