On the average site JS will add anywhere from hundreds of KB to over a MB of data to download: https://httparchive.org/reports/state-of-javascript#bytesJs

Especially when it’s foundational to how the site runs, e.g. the typical way how Vue, React or Angular are used.

I personally use a free (and small) mobile data plan, so that several MB/search would make me pay infinite times more. I switched to DDG.