Comment by twhb

Your JS knowledge appears to be severely outdated. Instead of the first you can now write:

    Object.assign(target, object1, objectN);

The second:

    element.classList.add(className);
    element.classList.contains(className);

And the third has been fixed at a community level, as we've learned the value of API strictness, obviating such checks.

I don't think anybody was against jQuery back when the alternative was helper functions, I certainly wasn't. But that's five years ago at this point. Modern JavaScript looks nothing like the code you posted, it's actually been built up into a pretty good language.