Technical SEO - How do you handle on page SEO for react/ angular/vuejs website?

Hey, I'm starting a broad discussion. Hope the folks from here can share their experience and add more inputs.

Usually these are used for back-end.

I'm using Vue on one of my project just like that.

The way I do it is Vue is on back-end set to noindex.

Font-end is basic, well optimized HTML (sales page). This is the page that actually ranks and brings in traffic.

Here is a popular example:
https://www.iwriter.com

I'm pretty sure they are using Laravel + Vue/Angular on the back-end. While front-end is basic HTML.