[vlakreeh]

With frontend a lot of what engineers are tasked to make (highly interactive websites that still have decent SEO and time to FMP), you need to add some complexity to achieve that. SSR + hydration for web apps has been common for years because it's great for SEO and getting a fast paint and because of that we now have these super established hybrid (as in client side and server side rendered) frameworks. Sure you can implement these sites with an html file and some JS to populate it with data, but it's hardly a nice and *easily maintainable* experience when dealing with non-trivial applications.

And now that your app is using one of these frameworks, you probably need some sort of API for whatever. There's a lot to be said about designing a REST api just being exporting an JS function in a file in a /api folder or whatever. If you are already using a hosted option for these frameworks it's an incredibly simple solution that doesn't require to you mess around creating a new project, making a docker image, going to a different cloud provider and giving them your credit card, etc. And depending on your scale that might genuinely be cheaper than running a container 24/7 on a public cloud.