Avoid enormous network payloads WordPress description

I made a [comment in the spreadsheet](https://docs.google.com/spreadsheets/d/1D4sz4NmhTjekJR2HIFX6QvO76c9PU2LHKDBf19YLnrA/edit?disco=AAAACgvtwSI), but I felt like it might be worth more of a discussion–

Typically when I run into the `Avoid enormous network payloads` detection in Lighthouse it's usually due to the content manager using overly large images or embedded videos.

The WordPress Description currently recommends reducing the number of posts and using excerpts which certainly wouldn't be a bad suggestion, but I think that would have more of an affect on TTFB unless there were many images within each post being queried.

Perhaps we could mention something about avoiding large images and large videos– possibly even recommending videos be hosted on services like Youtube to reduce their footprint on initial load? In my pull request I did add a note to avoid `Full Size` images in the WYSIWYG unless they are adequately sized. This could be relevant here too.