Selling performance is really really really hard. If we believe the "a product must be 10x better" chant, you'll need something that's at least 10x faster but is also as good in every other product attribute (UX, integrations, etc) ... and achieving and prioritizing those other attributes is usually what makes something slow.

There are exceptions of course, like where performance is the only product attribute that matters because you're doing something fundamental that can be made invisible to the end customer.