Reason 2 seems to be based on a lot of untested ideas about Chinese missile technology. It's true that the PLA has a very dangerous missile arsenal, but in the absence of any verifiable testing under wartime conditions some of the claims made in the video seem presumptuous. It also seems to assume the PLA will be able to launch missiles with impunity without the US doing anything to slow down the launches. 

Reason 3 is overly simplified. Overall tonnage and number of ships are far from the only ways to compare two different navies. You could also compare things like the VLS capacity of the warships in both fleets (where China has a growing advantage) or the types of ships available (the US has more carriers for example). 

Reason 5 seems to depend on the assumption China can convert their entire manufacturing capacity to war production. This is unlikely, a lot of industry just can't be easily retooled. You can't easily turn a factory that produces bookshelves to one that produces body armour for example. 

Reason 7 is entirely subjective. The videos shown to illustrate points seem to be cherry picked comparisons between official Chinese publications and amateur US social media posts.