1. becomes difficult to maintain large codebases for language-induced problems without multiple external libraries/frameworks/systems and/or expert practitioners.
2. code readability is all over the place (in contrast to, say, Python or Java). In fact, the best written JS I find to largely inscrutable. This is likely a personal failing, but I'm the one writing this list.
3. you have to write in a different language to get Object Oriented capabilities (eg. Typescript, Coffeescript). I'm inclined toward OO, so if I'm going to write in a different language, I might as well go all the way.
In short, amazing things have been in spite of Javascript, not because of it (not strictly true, since you can go nuts with the meta-meta generic programming in JS).
