That is not precisely accurate.
The GPL does not place any restrictions on how software is used, so the (literal) users are not restricted.
It restricts how it is redistributed.
Apologies, I intended "user" in my comment to mean "a developer using the license". Thank you for clarifying.
This is the core difference between gnu and bsd - guaranteeing freedom for all current and future users VS all current and future distributors (in particular, the bsd guarantees the right to fork and close - often seen as essential for commercial use in a new software or software+hardware appliance; while gnu attempts to guarantee that any downstream user will always have the four freedoms).
It's so easy to forget that at the very end, there are people who are using software. Developers are middlemen for most code in the products they build (think dependencies). GPL cuts through that, and always has the end-user in mind.
It's important to remember that GNU is Not Unix, but OpenBSD userland is much more so. There isn't much reason to protect future forks if you expect that future software should start from first principles instead of extending software until it becomes a monolith that must be protected from its own developers.