There are Thunderbolt based drive enclosures, but the reasonably priced ones are all based on one of a handful of USB to NVMe bridge chips. You usually get a 10Gbps link, so nowhere near the speed the NVMe drive inside is capable of, but about twice the performance of SATA-based USB drives or the fastest that use a USB-native SSD controller. Compared to a typical USB thumb drive, performance is night and day, especially for writes and random access.