If you really want to have a 90-100% score on gtmetrix on mobile hire a freelancer to make your store in AMP or Progressive Web App technology,
PWA i can do it my self

but why i do it ? any website now is mobile friendly ... nobody going to download your app, we are not aliexpress or amazon
I have a website which is PWA in my country, but is online store which operating over 8 year with stable customers, for this reason i make it like this.
score 90-100% do you really believe is matter ? then you are out off your mind ... just the onload time is matter nothing else .
the stores are very hard to optimise on Wordpress platform.
Is not hard at all ! i dont know why you say that . To a simple google search almost anybody can optimize them website now.
Maybe years ago when we use to make website with dreamweaver was hard , now with wordpress almost everybody become a developer.
Yes the CDN make a little bit of difference if you know how to set together with your store and plugins.
OMG thank for the info

Please you dont need to try so much to prove your self.
also the PWA is not gonna help you get a score of 90-100% , actually is slow down the site , please dont give incorrect information because and other member see and follow our thread!!!