First: Good job on the author! I don't think I could make 300 application in a three months, and I am fortunate that I have never needed to. This is impressive determination and focus, and it paid off.
Second: Wow, programming is becoming a commodity. This is literally 1) Learn the latest trendy framework and nothing else, 2) Study to the test, 3) Interview well. Either the market will be flooded and salaries for generic JS devs will crash, or strong programmers need to find a way to differentiate themselves that cannot be copied by anyone in 2 months.