pg_upgrade as a way of cloning an instance?

Hi all,
someone pointed me out that pg_upgrade can be used to do a clone of
the database, specifying the same binaries such as

pg_upgrade -B /usr/pgsql-13/bin -b /usr/pgsql-13/bin -D /data/clone -d /data/src

I tested it and it seems to work, even if I don't see any point in
running it (and most notably it requires a downtime on the original
cluster).
Any opinion about that?

Thanks,
Luca