I think the issue fundamentally is that this isn’t what terminal emulators are. The terminal emulator initializes a TTY session and enters a shell environment (sh, zsh, fish, etc). The medium is text and cannot be anything else.
This is 90s thinking. Why must terminal emulators only be text and only do things that a physical terminal could? What makes teminals so nice is not that they work on 90s technology. Some terminal emualtors can already display images. Which is great. And the ideas they are introducing are still fundamentally text based, but are geared towards structuring that texts a bit more than a constant stream of characters on the screen.
Skill issue. Pipe your output to something (like a file or the “less” command)
This is a convenience issue not a skill issue. Yes you can pipe output to things but you need to know before hand that you want to do that. And with less you lose that output once you close less. And with files you have to clean them up after the fact. Both of these are inconvenient and need to be thought of before you run a command. IMO it would be nice to just run a command and then be able to collapse or expand or search its output after the fact and not have to preempt everything beforehand.
The argument that you can already do that in a much less convenient way is not a very good argument.
TBH I am starting to come around to the idea of a tightly integrated shell and terminal emulator support. There are just things you cannot do with these being separate things. I am very tempted to explore the idea from the other end though - writing a shell that has a emulator built into it (like screen/tmux basically are). But I do think that this integration is needed for any per command features that is not just printing out a prompt.
It would be interesting to see what could be done with this type of integration but will likely break support for existing shells. Unless you maybe launch a shell for each command you run or something 🤔. Would like to seem more people experimenting with stuff like this and see what new things we could drive forward. We have been stuck with the current tty system since like the 80s to support devices that just dont exist anymore.