I’ve used Plex DVR and Emby DVR to record OTA programming with an HDHomeRun. Works great, just like you’d expect a TiVo to work.
With Plex pass and a tuner like an HDHomerun you can record directly to your servers storage. It’s not terribly difficult to setup and works really well assuming you get good OTA signal. Of note the HDHomeruns seem to be less sensitive overall to OTA signal and anecdotally have a harder time pulling in ststions with birderline signals.
A place for those looking to get away from the traditional cable tv model, and move toward cheaper and legal options like over the air antenna, library collections, and streaming services.