Hibernate does not save you from writing queries. You are still writing queries, just in a language different than SQL (e.g. JPA). It's an abstraction layer. The problem is that this abstraction is very leaky, so if you really want to write performant code with Hibernate you do need to understand how SQL and your database works. And if you really understand how it works, you end up realizing that the abstraction is kinda pointless because SQL is already a really fine abstraction over your database.

And if you need to scale, for example working with a replication setup with multiple db servers and having to deal with eventual consistency, then Hibernate really complicates things.

I think Hibernate is a good example of something that makes things easier at the beginning. At the cost of enormous complexity and difficulty in the long term.