I feel like Aurora might be a bad example for anti-lock-in. Perhaps vanilla RDS Postgres would be a better one?

Aurora does add bells and whistles on top of vanilla Postgres that you’d be hard-pressed to find from other DBaaS vendors.

Sure, you can pg_dump and pg_restore to another provider but you lose all the goodies that made you choose Aurora in the first place.

For clarity, I’m a long-time happy user of Aurora and spend $super_big_money on it. Worth every penny IMHO.