It is absolutely worth the cost and complexity. The cost and complexity of building a web application using some home grown vanilla JS system will end up being a horrible engineering decision most of the time.
There have been zero times in my career where I thought "hmm, maybe we shouldn't have build this thing in React and let's just go back to page scripts." If you're building landing pages and websites, then okay. But that's not most of what we're all hired to build these days.
There have been zero times in my career where I thought "hmm, maybe we shouldn't have build this thing in React and let's just go back to page scripts." If you're building landing pages and websites, then okay. But that's not most of what we're all hired to build these days.