There were comments about security risks though, based on being a small project with a LOT of integrations.
time will show, but the only thing i actively regret adding was the support for discord embeds (the "og" option); opengraph is an awfully designed concept and, unrelatedly, it has been a source of a handful of bugs in how it was implemented in copyparty (that one's on me). Keeping that disabled avoids a lot of edgecases, most of which are decreed by the opengraph spec.
That said, there's no features keeping me up at night; i think for the most part things are fine -- just don't enable the smb server 😁
The best and recommended way to connect to copyparty (either from windows, linux, or macos) is with WebDAV -- this will give you much higher performance. WebDAV is also a MUCH safer choice when connecting over the internet, since it is just https after all. Meanwhile, exposing SMB to the internet is generally a recipe for, well... nasty surprises :-)
There are also very copyparty-specific reasons to not use the SMB-server, and these are explained in the readme. That's also why the SMB-server is not possible to enable in any of the official copyparty distributions without manually obtaining the necessary dependencies for that (impacket).