As someone who has never used serverless functions before..

Netlify functions are based on AWS lambda functions, which spin up a container with say a node.js runtime environment everytime a request (or another event) comes in, then executes the user provided node.js function within the runtime. I can imagine that handy for something like cronjobs or api requests which happen occasionally.

But using Netlify functions for things like Next.js SSR (or API routes) means, that for every single website request, a new container is setup, the function is run once, and the container is discarded. Am i right in this? Isn't that a huge overhead in contrast to a long running server process?