JQuery is orders of magnitude slower than vanilla JS. It’s not about download time but execution time. I am not deliberately trying to punish my users.
Do you use React? In my experience, people arguing against jQuery are usually simultaneously arguing for React as a replacement for it, and are therefore arguing for replacing a ~30kb library with multi-megabyte bundles of catastrophically broken SPA code.
Why do you think you can only write multi-megabyte apps with react? And why do you think those two are the only options? You can write decently sized react code that's 300-500 kb bundled and if you're not ok with that you can start dynamically loading dependecies. Companies just choose to not spend any time optimizing it.