Has anyone else heard that Google Pagespeed Insights doesn't actually measure the phsyical speed of your website, but more the technical speed ? Not really sure if this is true, or makes sense. For example, GTmetrix goes into more detail about when the site is fully loaded.
Yea, we are seeing the technical speed as the metric used. With the load speed reported as being the time when the entire site loads, rather than the time it takes for the user to visually see what they would consider a "fully loaded" page.