I'm a former 4,1 user, myself — replaced with an M2Pro mini Jan 2023 (finally retired fully 2025).
Absolutely recommend you purchase the 4-bay Terramaster external enclosure — gives you four SATA slots that are hot-swappable (unlike MacPro's). 10gbps via USB-C.
It does not appear that SMART is supported on either version of my TerraMaster enclosures.
Still an inexpensive solution to help ease your transition away from MacPro"5,1"land.
As USB-C is a physical form factor (capable of supporting multiple protocols), I would think that the ability to have multidrive external SMART support would be up to the vendor's choice of datachip/datastream. Again: my Acasis does support SMART for nVMEs.
Absolutely recommend you purchase the 4-bay Terramaster external enclosure — gives you four SATA slots that are hot-swappable (unlike MacPro's). 10gbps via USB-C.