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.
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.
SMART is supported on my external Acasis nVME.
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I have two TerraMaster sledbads; this one [typing] is years older [only 5gbps, macOS Ventura] and shows `SMART: not supported` [1]
[1] It's mirrored WD_blacks (RAID1) so I have at least some redundancy... I know: a RAID does NOT count as "backed-up".
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Within an hour I'll have checked the newer system (I suspect it'll be similar — definitely faster!).
#TodayIlearnt
If you're self employed, the cost of equipment and depreciation make hanging on to that 2009 system even more of a poor choice.
If you were still using a 2009 system I don't see why you'd "have to replace in 2-3 years."