port sets echo for stty in at least one case

[ballapete (Peter "Pete" Dyballa)]

In GNU Emacs (different versions on Monterey and PPC Leopard) I encounter

root 297 /\ port -v
MacPorts 2.8.0
Entering shell mode... ("help" for help, "quit" to quit)
[work/test] > 
Goodbye
root 298 /\ pwd
pwd
/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_graphics_netpbm/netpbm/work/test

And similarly on Leopard where I tried to see a difference between quit and Ctrl-D:

ete 262 /\ port -v
MacPorts 2.8.0
Entering shell mode... ("help" for help, "quit" to quit)
[Users/pete] > 
Goodbye
pete 263 /\ apropos fls
apropos fls
ffs(3), ffsl(3), fls(3), flsl(3) - find first or last bit set in a bit string
pete 264 /\ stty -echo
stty -echo
pete 265 /\ port -v
MacPorts 2.8.0
Entering shell mode... ("help" for help, "quit" to quit)
[Users/pete] > quit
quit
Goodbye
pete 266 /\ apropos fls
apropos fls
ffs(3), ffsl(3), fls(3), flsl(3) - find first or last bit set in a bit string

echo can be switched off by stty -echo.

[ballapete (Peter "Pete" Dyballa)]

It plays no role in which variant of GNU Emacs I perform this simple test (X client, NS variant Emacs.app, Mac variant EmacsMac.app, or without own windows in Terminal), or which version (27.x, 28.x, 29.x) I use – the result is always the same. And it also "works" on High Sierra.