No, I don't think it's wrong to think older anime is better and I tend to agree tbh. I will acknowledge that yes, there is still good anime being released, but it's getting a lot harder to find really good stuff (For me it is anyway).
Obvious technical differences aside (Hand drawn cels vs. digital), I think when it comes to the argument of older anime being more "soulful", a lot of people tend to struggle to articulate what they mean by that, but I think I may have an idea.
The anime industry, much like Hollywood, the gaming industry and many other things, has become such a homogenized field in the sense that most anime being released now is solely being inspired by other anime. No longer are we getting series that present an author or directors unique ideas and worldview, or stories based on/ inspired by life experience, interests etc. we get stories from otaku who have no real life experience or interests outside of otaku culture and what surrounds it. All their stories have the same structure, same type of character archetypes etc. because they think that's how you have to do it because that's all they have to go off of. It just creates an all around insular industry with no real sense of growth like it once had.
I want to make it clear that despite what I just said, I don't think it's inherently wrong to be an otaku or take part in said sub-cultures. Some very open and unapologetic otaku have made some of the greatest works the medium has ever seen (Hideaki Anno and Hiroyuki Imaishi for example), but they still had their own unique worldview and ideas outside of anime that informed and enhanced their works.
I suppose at the end of the day it's kind of a reflection of the real world; most people are living mundane lives, no matter where you live or what you do, it's ronically one of the few things most people can relate to eachother with now. I think perhaps this bland era of media we have right now is a sideffect of this modern world we live in.