Sure, and we could all just design our own chips, hand code our own binary to create our custom programming language we use for everything... But humans have a neat ability to benefit from other humans' work.
An attempt to compare writing JavaScript to designing our own chips is a typical response I see from certain individuals online all the time. No knowledgeable person would ever do such a thing but I see it on reddit, and other amateur forums, all the time.
Sure, and we could all just design our own chips, hand code our own binary to create our custom programming language we use for everything... But humans have a neat ability to benefit from other humans' work.