Except Cobol didn't suddenly gain a lot of popularity after C++ was well established. There are plenty of languages even more abstract (and I would argue easy to use) than JavaScript, some of which don't sacrifice nearly as much performance.
The movement to JavaScript is a product of web developers branching out into other areas (great!) without taking the time to learn another language (not so great :/). I don't think performance is an end in and of itself, and I don't turn my nose up at picking a technology because developers and expensive and processing power is cheap, but I still think writing everything in JavaScript is a step backward.
edit: Accidentally wrote developers are cheap and processing power is expensive :P
The movement to JavaScript is a product of web developers branching out into other areas (great!) without taking the time to learn another language (not so great :/). I don't think performance is an end in and of itself, and I don't turn my nose up at picking a technology because developers and expensive and processing power is cheap, but I still think writing everything in JavaScript is a step backward.
edit: Accidentally wrote developers are cheap and processing power is expensive :P