It’s just before Christmas in 2018, and YES, it’s still possible to filter out most foul language on modern TV’s when you use a Tivo Roamio, which is a cord-cutters solution of a DVR which records Over The Air TV, and has commercial skip for many shows.
On the back of the Tivo Roamio, there’s a yellow jack that looks like a headphone jack. On eBay, you can find a NEW TiVo Roamio Composite Cable – For use with TiVo Roamio, Roamio OTA that plugs into that yellow jack, for $15.
Buy the TV Guardian 501 HD, and plug the loose yellow RCA connector into the back of TV Guardian Input #1. Follow other setup info in the TV Guardian manual, for the Tivo HDMI cable and the TV HDMI cable.
After setup is complete, TV Guardian will mute the audio as it sees Closed Captioning text with foul words, and provide edited close caption text if desired.