Material Files has an ftp server built-in and can also access SMB shares.

Windows File Manager has ftp access built in. Start the ftp server on your Android phone then in File Manager address bar, just type:

     ftp://[phone IP:port]

The ftp server will present this info at startup. Assuming both your phone and desktop are on the same network, the connection is easy.

Once connected, you can access just about anything on your phone from Windows desktop.

It is really a weird way to find out that they have stopped supporting File Transfer

I'm using ftpd server on my phone to copy files off/on.