I don't disagree that providing ML-features-as-a-service in a general way is much harder than a normal SaaS business. However, I don't necessarily believe those

I don't disagree that providing ML-features-as-a-service in a general way is much harder than a normal SaaS business. However, I don't necessarily believe those sorts of companies are the future of commercial ML. Rather, I believe practices like transfer learning and improved infrastructure (see the turnkey inference platforms mentioned previously) are enabling startups without armies of PhD's to build these ML-powered features themselves.