I believe there is a shortage of what I consider to be real database developers. It seems to me that most database performance issues are addressed from the perspective of platform and operations: migrate the server, tweak the server, scale-up, scale-out, etc. However, these things either have zero impact or at best can provide only a 30% improvement at the expense of doubling the operational cost.
Addressing the root cause of the issue, meaning analysis and optimization of the SQL code, tables, and indexes; that is only seen as a last resort or maybe never considered at all, because the skillset doesn't exist in-house. But that's what gives you the 10x yield you're truely looking for.
"Do not seek to follow in the footsteps of the wise. Instead, seek what they sought." - Matsuo Basho