I disagree, at least with regard to the “front end tools” that the author is using “React” as a stand-in for, since I’m more of a Vue fan.
I actually just built a small website (seriously, it’s three pages right now and doesn’t even have a contact form at the moment, it’s that small and simple), and I found three use-cases so far to justify Vue and zero for jQuery.
One word: reusability.
I literally have zero data being transferred right now, except the initial page load. I’m leveraging Vue’s single file components feature, which allows me to build the segment of a thing, add a couple of configurable options, add behaviors and animations, and have it all wrapped up in a self-contained component.
I’ve got a large parallax effect going on, and the page that’s holding it contains 10 lines for that segment, where it would take 10 lines for each segment of the parallax, just for the scaffolding (not including content). Without the component setup of Vue, 50 lines (granted, with a fair bit of whitespace) to my CSS, plus however many needed in a JS file to handle what my component is doing in two lines.
I’m in the process of building that contact form at the moment, and it’s housed in a Vue component, so that I can use it on more than one page, let it adapt to different sizes and backgrounds, use AJAX form submission, etc. all without trying to keep a sane structure in my global JS and CSS files.
The front end developers at my office are also starting to build Vue components that they can use across projects, to increase their efficiency.
To me, saying “you don’t need React/Vue/Angular until your site gets huge” is kind of like saying “you don’t need a structured programming paradigm (such as OOP) until your project gets huge.” Why not make it maintainable and modular from the beginning, especially when it means you get stuff that you can then reuse across projects?
Also, jQuery solves a different need from Vue, React, et al. and aren’t really either comparable or mutually exclusive.
I highly recommend a) challenging yourself to a project that avoids jQuery, so that you can see what’s available out there now (because really, 99% of what jQuery does can be done better natively or with smaller dedicated libraries), and b) give React and/or Vue and/or Angular a fair try before dismissing it for all but very large, complex sites.