YouTube viewers are set to see a big drop in video quality worldwide in response to the COVID-19 pandemic. This does not mean the YouTube TV service, just the regular free Youtube video service.
YouTube will reduce the quality of all videos to standard definition as a way to alleviate internet congestion due to more people having to shelter in place and using the service.
YouTube says that users will still be able to switch videos to HD and other high-quality options, but standard definition will be set to the default no matter how much bandwidth you have. The site will be implementing the streaming quality measures over the next few days.