OWC's Upcoming Thunderbolt Hub Adds More Thunderbolt 3 Ports to Your Mac

Thunderbolt has been out for like 9 years. Can someone explain why all of these hubs are still so expensive?

I'd consider myself a pro user, and I've been using a MacBook Air M1 with 8-core GPU and 16GB of RAM and couldn't be happier. A product like this that can add more Thunderbolt ports is the cherry on top.

.. i didnt think you could split thunderbolt.. i thought you could only daisy chain it.. what kind of devils magic is this?

The description references Thunderbolt 3 and the images are labeled with Thunderbolt 4.

Because electrically there is no difference between TB3 and TB4. TB4 is more of a certification, it requires full TB3 feature set in the host, along with secure memory access which wasn't present in older host controllers. They added hub support, but apparently there wasn't anything preventing it before in the protocol.

TB4 spec says can support 2 4K displays. So new Apple Silicon M1s must be TB3.
https://images.anandtech.com/doci/15902/Intel%20Thunderbolt%204%20Announcement%20Press%20Deck_070720-page-013.jpg

Thunderbolt v4 is a bit skewed toward Intel. Not too surprising. Their gen10 and gen11 U series processors with integrated TB controllers have a four DisplayPort v1.4 stream attached so meet the spec. ( also all get a clean switchedd x4 PCI-e v3 feed also) . But it is also more uniform. If it is a TBv4 system then it doesn't matter which port you choose it will always have a video signal present. ( so you don't have pull out your USB4 symbol decoder ring to find out which feature is on which port on which system. ). TBv4 is largely about not having to worry what part of the optional parts of the USB4 specification the system implementer skipped.


There was a recent posting the seemed to indicate that Apple's integrated TB controller has the baseline ability but just isn't fed the four streams from the internal iGPU. So the M1 comes up short probably based on having a limited iGPU.
Insert a more capable iGPU into the Apple Silicon die and then Apple could get the TBv4 label ( if they bother to go through certification process ) .

Just to clarify a few things...

USB4 is largely based on Thunderbolt, however, there are material differences in regards to implementation (signaling rates, power delivery, etc.). Thunderbolt 3 interoperability is optional, not required, for USB4 hosts and devices.

Thunderbolt 4 is USB4 with mandatory Thunderbolt 3 interoperability along with a bunch of other minimum requirements to achieve certification. The Thunderbolt/USB4 ports on the M1 Macs are Thunderbolt 4 as far as signaling and power delivery are concerned. They do not meet the minimum requirement for video output because the M1 can only provide the Thunderbolt/USB4 host router with a single display stream. So aside from not supporting at least 2 displays, the USB Type-C ports on M1 Macs are otherwise Thunderbolt 4 compliant. This is not a deficiency in Apple's implementation of Thunderbolt/USB4, but rather in the display engine for the M1's GPU. Either port can drive a display, but not both at the same time.

The reason why Thunderbolt has historically been strictly a daisy-chain topology is that Intel never produced a Thunderbolt controller with more than 2 ports. You can't build a bigger switch/hub with only 2-port switches. That all changed when Intel recently released the 4-port JHL8440 "Goshen Ridge" ('https://ark.intel.com/content/www/us/en/ark/products/189982/intel-jhl8440-thunderbolt-4-controller.html') controller. OWC's device appears to be first to market and very reasonably priced, but I'm sure more vendors will soon follow.