yes but it is portable. On the lisps machine, you could not port to a different type of machine by another producer in general, even less across version. The Linux ABI is stable.
The whole motivation to develop Common Lisp (which is mainly based on the ZetaLisp language for the Lisp Machine) was to have a common language for application development and delivery across operating systems and machine types.
When the Common Lisp Object System was developed in the end 80s, it was developed for ~15 Lisp implementations, from Lisp Machines to Apple's Macintosh Common Lisp.
To give you a recent example: ASDF is a built tool for Common Lisp software. It's 13k lines written in Common Lisp. I have here literally the same source file (Version 3.3.6) loaded into SBCL (macOS 14.2) and a Lisp Machine (Symbolics Portable Genera 2.0.5, running on an iMac Pro): https://i.redd.it/h94h3emjap8c1.png
> The Linux ABI is stable.
That's only a part of the Linux fragmented eco-system: CPUs, distros, ... A few days ago I have installed the Linux subsystem for Windows 11 on an ARM64 machine. Obviously it is not that easy to get all kinds of Linux software running on it...