Have used Oracle for almost 20 years ( also sql server, postgres, mongo, redid, sqlite). The database itself is a great product and has a free and cheapish option. I've worked on major UK utilities, oil and gas and investment banking projects.

Many enterprise companies have multi-million lines of plsql and thousands of db tables. I've migrated some systems away from Oracle to "save money" but it costs a lot to move an entire business to a new platform while they are running in production.