I have nightly backups dumped to Cloudflare R2 from a GitHub action.
If Neon announces they're shutting down, migrating the database to another provider is a bash 1 liner and an hour of downtime.
If Neon just "goes dark" I can recover from the nightly backup and lose at most 24 hours of data - data that is denormalized into other systems and can be manually recovered if absolutely necessary (but probably not).
Not every company is the same, but for many use cases the database layer is an inconsequential decision as long as the API is fungible for your use case.
Not every decision is a 1-way door.
The most important way you can spend your time when making a 1-way door decision for a company isn't picking the right door. It's turning the decision into a 2-way door.