SFTP? Don't confuse it with FTP or FTPS - SFTP is a different protocol which runs on top of SSH.

What do you mean, "for what it’s useful for"? For me, WebDAV has replaced FTP where SFTP hasn't.

like in enterprise? the browsers stopped shipping with ftp support I think 5 years ago.

HTTPS has largely replaced it. Pretty much all files uploaded or downloaded from the internet is going to be done via HTTPS and not FTP.