As a Gen I fanboy myself, I actually couldn't agree more with this statement. The design of some Pokemon have ALWAYS been silly. I'm convinced that when they create Pokemon they just lock someone in a room and tell them they can't come out until they've cranked out 150+ new ones. I mean really? Tangela? "This one is gonna be a bush! Well uh, that's not creative enough, so let's give it eyes. Oh wow, uh that's kinda creepy and looks like a rip-off of Cloyster. Hmm...I know! Let's give him Jordan's! Yeah, that's great." Speaking of Cloyster, we all know that it's just an excuse to put a dirty girl part into the game XDAgreed. The people who say they like the original 151 best are welcome to their opinion, but when they say things like 'omg the new pokemon are so ugly durr durr overdesigned uncreative look like digimon blah blah', it's clear they don't really like Pokemon at all.
I have a friend who is one such person. :/ She REFUSES to pick up B/W and give it a chance because she says the new Pokemon are ugly and dumb and Pokemon should have stopped after 151 and omg misty and brock and ash.
They're PokeHipsters, really :/ You can't say you like a series if you're not willing to give the later installments of said series a try.
For the record, I try my best not to be the sterotypical "lolol you n00bs SUCK gen I is the ONLY ONE." And honestly, I feel as if Gen V has been SIGNIFICANTLY better than Gens III and IV in terms of being like the originals. I can understand why a lot of original fans gave up after Gen IV, because from an original fan's standpoint that one SUCKED. but it still brought in a new wave of Pokemon fans, and changed the direction of Pokemon to make strategy, competitive battling, etc. possible. If you take diamond and pearl for what it was and give Gen V a fresh look, I would say it's the best game since Crystal.
My main reason I love Gen I is obviously because I was around for when Gen I started, and it was my first game. Being around the "magic" that surrounded all of pop-culture of the time admittedly makes me a bit biased. I know it sounds EXTRA arrogant, but it's one of those things that needed to be experience. I don't criticize new fans though! I more feel bad for them that they weren't around to be part of things like Missingno and such that really made this series what is is today...
Either way, to conclude, no: Gen I doesn't have the best "sprites" or anything like that. But we also weren't overpopulated with legends, which in my opinion is one of the things that killed Pokemon.