Is your project using spring-boot by chance?

If so, the observed behavior is because Spring Boot overrides the PhysicalNamingStrategy and ImplicitNamingStrategy with their own implementations. Specifically, in org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy, you'll notice that the code eventually leads to applying lower case. Therefore, it really should be addressed by Spring because the default naming strategies used by Hibernate don't exhibit this problem.