There is a lot of hype that Thunderbolt 5 is 'just around the corner'
From the link.
"...
When is Thunderbolt 5 coming?
Intel hasn't yet shared any details on the availability of the next generation of Thunderbolt, but with an official teaser out of the way, we can probably expect it to happen sometime soon. New versions of Thunderbolt generally debut alongside a new generation of processors. We'll probably hear about 13th-generation Intel Core mobile processors at CES 2023, so that would be the most likely timing for Thunderbolt 5 to make its debut.
That's not a guarantee, however, and Intel could end up waiting for its next generation of processors to introduce it. After all,
13th-gen Intel desktop processors are already available, and those don't support Thunderbolt 5.
..."
CES 2023 came and went and not a peep about TBv5. Some rumors project that Gen 14 ( Meteor Lake) doesn't have TBv5 either. So that is end of 2023 - early 2024 timeframe right there. If TBv5 misses Gen14 then end of 2024.
[ Gen 14 was suppose to have a more capable TSMC N3 iGPU tile/chiplet. That isn't happening. So Intel is going to need a decent amount of dGPU support and a tighter overall chip package thermal budget. So while conceptually Intel could 'slap in' a late breaking TBv5 capable external I/O tile/chiplet at the last minute, it is more likely that most of the allocation for PAM4 like overhead communications will be aimed at internal PCI-e v5 traffic than at Thunderbolt. Puts much less stress on that inter-tile/chiplet bandwidth also.
]
Anyone who thinks TBv5 is coming before Intel can ship a SoC with TBv5 controllers inside is fooling themselves. Apple isn't a bleeding edge TB adopter. The second gen MBA doesn't have TBv4. Apple has also 'whiffed' at adding DisplayPort 2.1 also in second generation. (so no hurry there either. Major output leap was actually just doing couple year old standard fully complaint HDMI 2.1 output. ).
Throw on top the general PC market 'bust' phase after the pandemic 'boom' phase. Selling 'known quantity' TBv4 looks pretty good right now for vast majority of system vendors.
It is also pretty likely that Apple probably isn't looking to put that much additional stress on their internal chip backhaul mesh either. Any backhaul improvements are likely going to target GPU , CPU , NPU, and accelerator memory and/or inter-processor-cluster transfer throughput rather than wiz-bang TB ports.
It actually would help the long term Thunderbolt process for Intel to wait a bit for Qualcomm and/or AMD to pick up TBv4 before moving things to TBv5. Intel doesn't have the super tight monstrous grip in the Windows PC market anymore. In fact, if Gen 14 mobile SoCs don't correct the fall in mobile market percentage then Intel is in deep, deep , deep pile of manure.
Even more so than all of the above TBv5 can't arrive before USB4v2 does. It is just 'less optional USB4v2. Similar panademic disruptoin factors probably going to play out there. There are not 3rd party TBv4 perpherial controllers yet. The USB ecosystem has relatively barely adopted USB4. No USB4v2 hype train at CES 2023. Now that Thunderbolt is intertwined with USB standard evolution and adoption the rate of change is going to slower (i.e., if USB moves very slow then TB will take up the same pace as the larger inertia. )
The xMac with slots isn't 'padded' due to lack of demand. Similar effect of why most entry Apple SSD is priced at $400/TB. The free standing Echo III are not being made 'cheaper' by essentially putting the guts of one insdie the xMac Studio. If look at how much the TB enclosures cost and then at the rack versions they are on the similar range of prices ( more expensive with the rack infrastructure wrapped around).
Apple's defintion of Pro user was/is pretty expansive. By their definition the most popular "Pro" system is the MBP. But in 2017 the iMac was much , much bigger than the Mac Pro. So yeah by that metric might be talking about > 50%. But the reality of the situation though is that you and the other folks who are challenging your ">50%" have not actually agreed to what "Pro" really is. So more so the situation of multiple blind folks grabbing different parts of the elephant and 'perceiving' different things. ( it is tree trunk , a snake , etc. )
If talking about the historical and current hard core Mac Pro user base ... that 50% isn't going to hold up. Just on data storage expansion needs. One,
only one , internal drive is a folly in Mac Pro space. Apple even explicitly fessed up to that back in 2017. TBv5 isn't going to make the less true in the future. ( a four M.2 SSD PCI-e v4/5 add-in-card that aggregates the collection PCI-e throughput is going to swamp TBv5 also. )
), I can see Apple delaying the Extreme and initially releasing the Mac Pro with only an M2 Ultra. Then later this year upgrading the Studio to M2 Max/Ultra. Then next year, upgrading the Mac Pro with M3 Ultra/Extreme.
