If you want a speed test far better resources are:One of the best mobile tests is from Think With Google:
No it's not!Yes Amp is best option its latest and fast. I will recommended you to optimze CSS/JS/Images compress these following these will also help you boost your ranking in desktop version as well.
And I'm sure they've done a lot of other optimisations to the code to make it faster too.... (although I'll be honest and the site code looked pretty untidy to my untrained eyes)Please check the olx website, they are using AMP technology,And Amazingly its pretty much faster.
Please read the AMP specifications. AMP only applies to search results on mobile phones. AMP delivers pre-rendered pages on your phone. People looking at an AMP page don’t even visit your website. Ergo, AMP will not make your site faster.Please check the olx website, they are using AMP technology,And Amazingly its pretty much faster.