The database really isn't that important. It only becomes important once a DBA gets their hands on it and starts implementing LOGIC at the database instead of doing the logic in the application and fast, dumb, simple queries at the database.
That is not true at all. In fact wildly wrong. A good database is the tool you use to manage your data. If your system is properly designed, it is part of your application. A good database will manage concurrency, data integrity, and more. The idea that you move this out into the application geometrically increases complexity, or more likely, is ignored at your peril.
Just a simple query:
select * from songs where name like 'love%';
Assuming you have a non-trivial amount of songs, i.e. a song web site, this query can show a poorly implemented index. Once you start getting into sub-selects and joins, a good database can do quite well, a bad database, i.e. MySQL will fall down.
People who view the database as nothing but dumb storage usually end up implementing similar features in their code. They won't be as efficient, won't be standard, will cause the data to be processed more than it needs to be, and can't be tested as well as the database's system.
A good architect will know where and when it makes sense to do something in a database verses the application. Ignoring the capabilities of a database for some idealogical purity is ridiculous.