Another aspect of 30TB+ HDDs with a single actuator is their IOPS-per-TB performance. As capacity increases, IOPS-per-TB performance drops, which affects system responsiveness and, ultimately, quality of service. For large hyperscalers, mitigating this effect is not a problem. Still, this issue may become a problem for people serving traditional corporate datacenters or running an enterprise-grade NAS, so they might prefer to wait for dual-actuator HDDs of similar capacity.
Correct me if I'm mistaken about this, but... it appears that everything shown on the slide, including these 30-50TB drives, is part of their "MACH.2" line, which IS dual-actuator technology, isn't it?