I'm not a 100% sure what you're talking about but I think I understand where that picture is coming from :p
The reason I'm a bit harsher on the 2 follow up seasons is because I felt the show was trying to recreate mothers family homemade apple pie but without the actual main family recipe, what we got served an amazing apple pie that tried its best but it's just not the same as mothers family homemade apple pie. If they would have released these shows with a different title and character names than it would have had to carry less of the weight of the original season, this was a choice they made so it's obviously going to impact the viewing experience.
It wasn't as amazing but I'd still keep stuffing my face with it and I wouldn't say no if you offered seconds. I feel that's an honest and fair criticism. When the main people responsible for the first season say no to the new projects then wouldn't it make sense you're eating something that isn't totally the same experience.
I still love it but there is a difference between being awesome and being a masterpiece, As the creator said 'mself, it's hard to recreate that magic because a lot of it had to do with the time it was released in which is that whip cream on top of it all. :)
Kyubey from Madomagi was slightly different because he was a trickster, the character had a meaningful role as the messenger of magic to lure the young girls into signing a contract with him but you only see his true colors nearing the ending of the show if I remember correctly. So for most of the show Kyubey follows that role of the helpless but pushy mascot character.