Google’s video search results seem to be testing removing the YouTube channel name and video upload date from the search results snippet. I am not sure why Google would remove these important details from the search listings, but I guess Google likes to test these things.
Because they’re an ad company first and foremost. It’s more important to them that you open the video than it be relevant. If you have to open a few extra videos to find the right one, you’re more likely to see an extra ad or two in the process.
They don’t have to worry about the results being less useful until it’s bad enough people start actually using other search engines again.