This is worth considering, especially when you can get a DO droplet for $5/month and run whatever free software you like on there on Ubuntu. That has to be as un-locked-in as it gets. You could run the same thing from a Rasb-Pi at home!

I am happy to use Netlify as a static file host as that isn't much of a lock in: I can move to S3 later, or even the DO droplet and Nginx!