Another factor related to speed is that, they didn’t allow using NVMe slots for storage pool until recently for new models (in 920+ still you can’t do that; even if they allowed it, the limited PCI lanes of that CPU would limit the throughput). So a container’s database has to be stored in mechanical HDDs. Again other companies moved on, and I remember there were a lot of community dissatisfaction and hacks, until they improved the situation.

Their hardware is limited already, and they also artificially limit it further by software.

They changed course now, and allow using any HDD. Will DSM display all relevant SMART attributes? We will see!