“Let’s compare the before/after Timeline strips for the CNet’s Tech Today and Housing.com PWAs. We can see first view taking a few seconds over average 3G. Look at the 3–4 second improvement Service Worker caching their App’s Shell and data made to their loading times:”
Maybe I’m overlooking something simple here, but the screenshot below that statement shows a difference between first view of 1.5s, and a difference between repeat views of also 1.5s. So the difference is 1.5s, not 3–4s? How did you even come to that conclusion?
The Twitter example is equally confusing, as it shows no before and after. You cannot randomly mix first visits and repeat visits to make convenient conclusions.
And the same for the Flipkart example. Repeat visits are always way faster than first visits, with or without a PWA. If you do not include all 4 scenarios (first/repeat with WPA, first/repeat without PWA), there is no meaningful conclusion to be made.