I don't think scan recursively was ever in TV shows, I went back as far as XBMC, and it was always missing. Scan recursively is for sources that have a heirachy or sub folders that are to be scanned. TV shows obviously have a dedicated folder pattern, so the option is not required. Set content and scan(wiki)
FTW: Scan recursively
Scans sub folders for movies as well as the main folder. Great for if your movies are categorized into sub folders (e.g. genres, a-z), etc.
Example: /Movies/Action/Big Buck Bunny.mkv