The share options “read only” and “writeable” have the following defaults:

Default: read only = yes
Default: writeable = no

So, think of explicitly set write permissions if needed (or lose a lot of time searching why you cannot write, that happened to a err.. friend, you know :/).

Obey pam restrictions has weird side effects like using the default UMASK set on the host for creating files, which de facto overwrite the force create mode and force directory mode options. That’s also a good way to lose time searching why the permissions are not set correctly.

On some old configurations I found it set to yes, but the default is now no.

Default: obey pam restrictions = no

Source: https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html