I’m seeing some reader confusion on USB3 vs Thunderbolt.
For an external hard drive, Thunderbolt has no speed advantage over USB3.
Using Thunderbolt for a single hard drive is fine and indeed preferable (cable strength and durability), but to date Thunderbolt entails a cost disadvantage both for the enclosure and the cable itself (expensive). And when three or more drives are used in a RAID configuration, then Thunderbolt becomes valuable for its higher throughput and more robust cabling.
One thing that makes me nervous is using USB3 over a splitter or hub device—if that is needed (shortage of ports), better to add drives via Thunderbolt. Ditto for those narrow (thin) USB connectors.
Bottom line: the most robust and more complex systems should useThunderbolt, but USB3 with appropriate connectors remains an excellent choice for many uses (e.g. backup and single drive setups, travel, etc).