I can probably agree with a bit of all of them.
Ease of access has meant that the quality of online content goes down, as younger kids and normalfags could access the internet and post utter nonsense or ask stupid questions. That applies to all. I think that its gotten even worse as the phone generation has gotten into the net, as they didnt at least have to deal with some Windows issues or updating software outside their black box experiences on iPhone, Android or any other store based experiences.
The sites themselves have definitely suffered a lot due to mass migrations to exclusively a few sites.
It is hard to tell however whether lots of the users online these days would have used such sites with more niches like say newgrounds, or whether they would just do something else entirely, partially due to a lack of skill their end that is undeveloped, or even just the means (phones etc). I havent used newgrounds on mobile so i'm unsure how that experience is.
A lot of sites these days try to it all, and even discord has started becoming like that. What was originally just a decent group chat with the boys has become a reddit replacement, a github downloads replacement in some cases and other such. It is definitely where I see the net as worse these days. Especially since its not even open access.
Since I run this site and want it to succeed, get more popular and all that jazz. I do have to think about what kind of shape I want it to take and how it would impact the web. (im sure thats really gay to read). The site is broad but I think the general theme of 'hobbies' does at least let it have its limits. I did debate some kind of drama section because I do find a lot of that stuff interesting, but I know that can change a userbase when the perspective is changed like that. I think thats how we've managed to avoid some heated arguments so far. Same kinda with chat, I want us to have some more features for users to talk to eachother outside of threads, but I am becoming less warm on the idea of having some sophisticated chat system here. I may instead try to make it easier to get an XMPP account from the site or give users tools in that regard. I'm happy to facilitate friendships and such but I think if we can in some way get people using the cool tech we have already for their specific purposes I think it'll be easier in the long term and better for the internet as a whole.
WebRings are a neat concept, Image boards use them best I think since its functionally like an agreed fediverse. For this site I think maybe a page with 'friends of the forum' listed would be more fitting as we use accounts. Maybe if more users used the blogging feature the site would fit better into a webring.
We as users and as admins have the options to make the web better, it is just about using them and creating our own circles where the desires and habits match.