Twitter/mastodon require interactivity to keep users engaged. That is what differentiates it from old school forums. Keeping content short helps with focus as well since people want condensed information as fast as possible. You need notifications without having to reload the page to see other people reacting to your content. You need to see likes and shares alive so that you can see the platform is alive and people are active on it. Refreshing the page just won't do. You need to see new posts being written so that you see there is active conversation. None of this can work if one needs to keep reloading the page. Functionally sure, it will work, but it won't give the user the impression of being part of active group of people and engaged.
As for e-commerce website, you have live chat, various notifications, integrated payment gateway without the need to be redirected to dedicated gateway website(you CANNOT do it without js due to PCI-DSS). Yeah, it can be done with no JS but who would? And if that would be the case, the sales would most definitely reflect the lack of interactivity and functionality.
> You need notifications without having to reload the page to see other people reacting to your content
You saw my reaction to your comment on this site without any notification. The same goes for the old Reddit UI which is still popular enough that it's online after 5 years. A lot of people want to just have asynchronous conversations without getting distractions lobbed at their face all the time. I visit Twitter maybe a few minutes per month because all the autoplaying gifs and notifications on all sides make me sick. For me a lack of "dynamic" site content is a valuable feature.
> As for e-commerce website, you have live chat, various notifications, integrated payment gateway
The only interaction I ever had with live chat was clicking on it to remove it with uBlock, if I want to chat with a salesperson I can go visit a shop. Notifications? Not really necessary. Also 90% of the Amazon app's notifications were suggestions for products that can't even be shipped to my country! With all the data collection you might think they can filter for that but they don't. And you're right about the payment part but that's a tiny fraction of an online platform.
The problem with JS is not JS itself but the way it's often abused to degrade the user experience.
> A lot of people want to just have asynchronous conversations without getting distractions lobbed at their face all the time... I visit Twitter maybe a few minutes per month because all the autoplaying gifs and notifications on all sides make me sick.
Then you're not the target audience. Nobody goes to Chuck E Cheese and complains about the lights and noise.
> The only interaction I ever had with live chat was clicking on it to remove it with uBlock, if I want to chat with a salesperson I can go visit a shop.
I regularly interact with support on DoorDash, Amazon, and my bank using live chat, instead of having to get on a phone call and get put on hold.
> Notifications? Not really necessary.
I use a pinned tab for my email, which provides in-browser notifications for new emails and calendar events, so I don't have to install a third-party native app from some random developer (whose installation requires admin access to my machine) just to read my web-based email.
As for e-commerce website, you have live chat, various notifications, integrated payment gateway without the need to be redirected to dedicated gateway website(you CANNOT do it without js due to PCI-DSS). Yeah, it can be done with no JS but who would? And if that would be the case, the sales would most definitely reflect the lack of interactivity and functionality.