Days after calls in Europe for YouTube and Netflix to throttle, to help balance the Internet, YouTube decided to limit video quality automatically for EVERYONE. While you can change the resolution, please consider sparing the overall bandwidth, if you can see what you need to see. Remember that not having 4K resolution is a very distinct First World problem!
The next time you load up a YouTube video, it probably won’t look as sharp as you’d normally expect, at least at first. From today, videos will start playing in standard definition by default for the next month, though you can still bump up the resolution manually from the settings.