Thansks for the post I am looking to Purchase a Thunderbolt 4 Replacement drive and will connect directly not through a hub. I got a response on Facebook which was interesting and seemed to fit with my experience See below:
I think that the right solution is to move to Thunderbolt. Apple does not support the latest advances in USB yet (they may introduce support for it with the M3 Studio but I doubt it, as the controller is on the SoC and I do not think that M3 supports it).
So, Thunderbolt. M1 through M3 support Thunderbolt 4, which supports hubs (and not a speed increase from Thunderbolt 3). Hubs give you the ability to negotiate channels to the devices you have attached to the hubs but they do not increase the speed of Thunderbolt, as your controllers are on the SoC.
With respect to responsiveness in applications versus in the Finder, I believe the difference is in how the application accesses a file on an external drive versus how the operating system does. What you are finding is that the OS is highly optimized for Apple Silicon and the applications are not (or cannot be because they are using an API that is not optimized). Under the Intel Macs, your Thunderbolt connection was a discrete chip on the motherboard (made by Intel) as opposed to the controller on Apple’s SoC.
The way you get to your internal SSD is to go through the PCIe bus on the Intel system and on the new systems, you go through the SSD controller on your M2 chip (which is wicked fast).
When you are writing an application under OS X, your access to peripherals is virtualized—the OS is supposed to handle hardware. But, as I have laid out here, the access to hardware is different for the two systems. So, if the application is expecting to access a storage on a disk through a particular bus (old school is through the PCIe bus and not through Thunderbolt), it is virtualizing the wrong component. The command will get there, it’s just slower.
And, you get to USB through Thunderbolt or through the SoC’s USB controller, which may be more optimized for slower peripherals, like your keyboard.
So, what you are experiencing may be non-optimization in the application. This is why going with Thunderbolt reduces the likelihood of non-optimization.
But, beware: Inside a Thunderbolt cable are electronics designed to give you lots of speed through the bus. This is why Thunderbolt cables are really expensive and USB cables can be cheap. Some USB cables are designed to just charge devices, so they won’t carry data very fast (they will be really cheap ones). The specifications on what constitutes a Thunderbolt cable are tighter, so you will have to spend more for a Thunderbolt cable.
I am writing all of this so that you may fully understand what is going on and what the differences are.
