Have you even made a production grade front end project?

You can't use "pure" HTML solutions because every browser can display these differently. You have to use CSS to make a website look and behave modern. "Pure" center tag is clunky and doesn't work everywhere and that's "by design" (That behavior is defined in specification, and we can't change specification to meet today's standards because that would make it non backwards compatible). Additionaly you need to make your website scale to wide range of devices. And sometimes you need to even add JS to fix some of the issues if you don't want the developer to implement a non-maintainable solution taking him 5 hours, if he could do that in JS in 5 minutes.

Look CSS is not perfect. It's hacky solution to a problem, but news flash: most software engineering is. And it's proved to be working.

"But what if in the future..." - address future problems in the future. As soon as they appear - not before or after that.

That's the stupidest thing I've read today. I hope you're not any kind of engineer. There are some situations where it might not be worth it to future-proof something, but if you apply that to everything you end up needing a full rewrite instead of just adding a feature.