A webmaster was concerned about YouTube downloads. Adding these videos negatively affected the load time of their page by increasing it significantly.
In this case, while YouTube had a substantial negative impact, standard MP4 videos did not. This webmaster’s question was whether or not they should abandon YouTube altogether in favor of MP4 videos.
John explained that he doesn’t think it makes sense to switch to an entirely different format just for SEO reasons. You can always use lazy loading to make the YouTube videos load faster. One example you could use would be to set up a placeholder image. Once someone clicks on it, then the YouTube video loads.
This usually results in a decrease in page load time.
He also recommended making sure that you add the structured data for these videos.
This occurs at the 29:11 mark in the video.
You can also read the transcript below: