SAMBA Problems

I used to use SAMBA quite a lot - Linux servers
in a mostly-Win office environment. It was easy
to set up, offered fine-grained control options.
Point smb.conf entries at most any folder and
it would share it without issues.
BUT, starting with some Bullseye and esp now
in Bookworm, what Used To Work just DOESN'T
seem to work anymore.
I set up an SMB user, set the password. Set the
target folder permissions kind of, sometimes
VERY, liberally.
Would-be clients can see the server. Can see
the shares. However trying to ACCESS the shares
by 'mount cifs' or any other means always
results in either a blank, or usually some
species of 'permission denied'.
OK, what the hell changed so radically ???
Have perused many online tutorials, no luck.
This is not just one machine ... both PIs
and AMD64s are both reluctant.
CAN do NoFileSecurity shares OK - but SAMBA
offers a lot more nuance. All my boxes are
Linux.
Today's need is to mount an external multi-disk
usb drive. Bookworm does NOT seem to automount
those on reboot. DID find a code snippet that
resets the bus, and the external drives mount
at /media/user/xxxx as expected. I'd LIKE to
point SAMBA at those - ez-peazy. However I
could mount the /dev/sdx somewhere else after
boot by direct command, create symlinks or
whatever.
Oh wow ... this is an actual LINUX question :-)