That's why I said WP Rocket has better JS handling than Flying press...

I do understand what each item there means, bruh...
"TBT - How much time is blocked by scripts during your page loading process. A good user experience is 150ms or less."
And the site definitely feels faster on WP Rocket... I tested before posting my opinion here.

I test on 3 nearest locations of where the server is located. The screenshots I shared are the test results of the nearest to the server.
Of course, I'm very much open to the factors involved that's why I'm testing some more.