You are ignoring browsers support. One of the main reasons I suggest using jQuery is browser support. Another solution is to use a transpiler like Bable.
At this point in front-end development something like Babel is a must. If you aren't using Babel/Flow/Typescript in your workflow, you are putting yourself at disadvantage for no good reason.
For better or worse, transpiling is a fact of life.
If your Uber-for-toothpaste startup doesn't care then fine. But crusty old browsers are still a crucial factor in many markets.
This situation is actually improving too. Chrome's "evergreen" development cycle has made a world of difference to feature adoption rate, and it's spread to every other major browser vendor. Once IE11 dies out, we'll have no non-evergreen browsers over 1% market share, and it makes me so happy to say that.