We had a Sony Wega TV CRT that had a special "16:9 Enhanced" anamorphic mode that basically narrowed the vertical scan area of the electron gun while keeping the same number of lines. For a while you could find specially mastered DVDs that digitized the source material at a higher than normal vertical resolution. If you played them on a normal TV, everything would appear vertically stretched. If you played them on the Wega (or other similar TVs? Were there others?), then the picture would be scaled down correctly and would appear super sharp and bright.
That just seems like normal anamorphic mode but I guess built into the TV? DVD players would do it for you too so long as you set the aspect ratio in settings to match your TV. Otherwise an anamorphic wide-screen DVD would be basically unwatchable on 4:3. DVDs were often released as Full Screen (4:3) or wide-screen editions which were typically anamorphic unless it was poorly done.
[0] https://www.manualslib.com/manual/321453/Sony-Wega-Klv-15sr1...