There might be problems with Thunderbolt docks and monitors, I have no experience with those.
On the other hand, I have used continuously during the last 5 years Thunderbolt SSDs from several brands as my boot and working drives (i.e. without using any internal storage), with many computers, mainly Dell laptops and Intel NUCs.
Besides obviously being faster, the Thunderbolt 3 SSDs have been far more reliable than the external SSDs using USB.
So there is at least something that works properly, but I do not know if that is also true on MacBooks, because I have always used Thunderbolt only in Linux.
On the other hand, I have used continuously during the last 5 years Thunderbolt SSDs from several brands as my boot and working drives (i.e. without using any internal storage), with many computers, mainly Dell laptops and Intel NUCs.
Besides obviously being faster, the Thunderbolt 3 SSDs have been far more reliable than the external SSDs using USB.
So there is at least something that works properly, but I do not know if that is also true on MacBooks, because I have always used Thunderbolt only in Linux.