Hacker News is purposely utilitarian and that's fine but I don't think general audiences would tolerate it. You have to manually check if someone responded to your comment. I don't think its too unreasonable to say that most users expect a notifications system on a platform like this. Editing a comment takes you to a separate screen and leaves you there once you're done, you have to manually navigate back to the discussion you were on. Reddit lets you edit your comment in place and continue from where you left off straight away.

These features could be feasibly implemented using jQuery or plain JavaScript but the more niceties like that you add, the more you can make the argument for UI frameworks.

When reddit switched to their new 'featureful and rich' ui they provided a way to access the old user interface which is much more utilitarian and flat.

I expect most experienced reddit users still use the old ui toggle. I expect new reddit users don't know it exists but would probably prefer it once they got over the 'change is bad hump'.

The fact that years later the old ui toggle is still present is a testament to how much the new richer ui failed for their power users.

It seems to me you're confusing HN's lack of some common forum features with the way that those features would be implemented; I would imagine that if HN did get, say, notifications, they would largely work without javascript, or some big complicated frontend build process.

old.reddit.com is another good example. Not everything needs to be an SPA.

The parent suggested HN as an example of an application that didn't need a lot of client code. I think its still fair to say that it doesn't have many of the features that ordinary users have come to expect.

Old reddit is a much more reasonable suggestion. It is fairly feature rich and is used by a large group of users. It seems to deliver ~340KB of Javascript. It's pretty nicely minified so I can't tell what its all related to but at least some of it must be related to the interactivity that HN is missing.

Like I said in my previous comment, you can do as old Reddit did and build up Javascript to solve these problems but at some stage it might make sense to jump to an SPA. Reddit made that decision. I think many would argue that they prefer old Reddit which is fair enough.

I think its hard to say if the Reddit team made the decision based on a legitimate and provable technical need and their old solution just wasn't cutting it or if they went the SPA route because "its what everyone else does" and "its easier to hire React devs".

old.reddit.com works without javascript, notifications and all.

I tried there and upvotes, replying to comments and editing comments don't work. I can't speak to notifications but I'll accept that they work.