I can just use VS Code.
So how many VS Code extensions have you written? How many workarounds have you invented to make your workflow more productive?
Do you use VS Code for automation? Does it run any tasks for you?
Can you for example open a page in your browser, send it to VS Code instance and let it collect all the links on that page and show them?
Can VS Code work as a window manager? Email client? Maybe RSS reader?
Do you read PDFs in VS Code and make notes and annotations? What about epubs? djvu maybe?
Do you do project management in VS Code? Is there a way to calculate the number of days between the two dates? Convert that to hours?
Do you test HTTP requests in VS Code? Can you send a request, then feed the results to a Python Script, then based on that - create a SQL query and send it to a DB, then transform the data with Clojure and finally create a table with the final results? Can you do that in VS Code? Because I do something like that in Emacs quite often.
Do you plot sequence diagrams in VS Code? Or do you write math formulas? Do you work with research papers? Does VS Code have support for scientific citations?
What about prose? Do you write plain text in VS Code? I'm typing this in Emacs. I have syntax and spell checkers, integration with Grammarly (I know VS Code can do that one); I have Google translate integration, have dictionaries and thesauri.
What about some advanced version control? Can you change the editor settings depending on what git worktree you're in? Can you select a few files in the directory tree and see the git log pertaining only those? Can you edit the directory tree using regexp-replace or multiple cursors, or do something like "find all the files larger than 3Mbs that were created between two days in March, and rename them all?"
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Whenever anyone claims that they can perfectly do anything that you can do in Emacs, they probably have no idea what you can do in Emacs.