Can Google.com and other heavily trafficked websites get a “fast” rank using Google's PSI API?

Question

Google changed its PSI definition of fast-ranking FCP from 90-percentile to 75-percentile below 1000ms

From PSI documentation:

Answer 1

You are misinterpreting the google lighthouse results. First of all, no performance test is absolute. It's impossible to have a fully 100% performant page simply because even if it loads in 1 second for me, it might not load in 1 second for a person in Ghana due to network issues and delays. Even if I have a pure HTML page with no javascript which is served as a static file from a super fast web server, that page might load in 10 seconds for a person with a dial up internet somewhere in Cuba or Jamaica.

Heavy traffic simply means "I get traffic not just from USA or Europe where the internet is blazing fast, I also get traffic from Jamaica where internet speed is a joke". Every serious web application has this issue. So yes, there is little room for improvement because you do everything right - it's a local internet issue.

I guess this immediately translates to a sociological/political "first world problem" mind set issue. You are obviously living in a first world country or at least have 3G/4G internet and you can't imagine that people in Jamaica have 2G internet. So don't fret about the lighthouse percentages. Making a web site fully 100% performant which loads in under 1 second anywhere on the globe is impossible due to technical limitations of that country - impossible for you to fix.