Did you copy-paste an hallucinating LLM?
MS-DOS 1.x did not have subdirectories.
That came in with MS-DOS 2.x which is when the very rudimentary level of Xenix compatibility came in: device names such as `LPT1:` or `COM2:` could be prefixed as `/dev/lpt1` or `/dev/com2`. Pipes simulated in COMMAND.COM.
I don't recall DOS ever accepting command switches prefixed with `-` instead of `\` as standard, though.
https://forum.winworldpc.com/discussion/comment/171783/#Comm... (devices in \dev, "-" as switch char, etc.).
> While MSDOS had subdirectories, pipes were not supported at the kernel level. It was simply a convenience of COMMAND.COM that simulated pipes by running each command sequentially.
You are confusing the lack of concurrency with lack of pipes -- the mere fact that COMMAND can do what you describe requires UNIX-like pipes and channels (e.g. stdin/out/err), and programs avoiding direct console I/O (way common for DOS programs...). Comm software such as Kermit did the same thing to simulate remote login (I used this one in the day, at least).
Hardware requirements.
For a (quite long) while the plan was to keep DOS for microcomputers and Xenix for the serious stuff. DOS gained some extensions that made it very Xenix/UNIX-like (like subdirectories, pipes, "-" as command line switch char, device files in "\dev" instead of a global namespace, etc.).