Unless a person quotes my post I have no idea if someone is responding to my specific post
The seemingly unofficial etiquette here is if you're referencing someone's post, then quote it, either entirely or portions of it, as I have.
Additionally many of us also use
which triggers a notification.
Finally, most people tend to stay active in threads, so they read subsequent posts. Is there a risk that we miss someone typing something I said with "" instead of using [ quote ] tags. Yes, there's a handful of members who purposely chose to use "" and thus we're notified unless we're active - that's a risk.
Now with that said, even with nested replies, you have to stay active and read through the threads, so I don't believe you're gaining anything with the nesting other then making it harder to follow imo