Hard to say. When Dell came out with their 5K monitor based on the same panel, it wasn’t possible to drive these except via dual DP cables. There is enough bandwidth on USB-C DP Alt Mode to easily drive 5K on a single cable and any new GPU in the last 2-3 years can drive it.
Getting the 5K 10-bit video over the cable isn't the major issue with the "downstream" ports and internal camera on the monitors. It is more about what is left over when finish with that video pull. If using DSC compression then USB 3.1 gen 2 for a port is reasonable expectation setting. Come here to plug in your 30Gb/s external SSD probably won't match those expectations with good results.
And with more folks wanting > 60Hz the video becomes a Thunderbolt hog.
That said, it’s not like there hasn’t been a fully tooled assembly line for the 5K panel driven by guaranteed volume from Apple for many years that couldn’t be leveraged. The controller boards for driving these from PCs via DP 1.4 have been available on AliExpress for years - theres been a few smaller vendors who actually shipped monitors based on them (Iiyama, Planar)
But I think Dell, Ilyama , etc have all dropped out over the extended period of time. There were others at the initial several years. However, over time it has become pragmatically an Apple only resolution.
and even a few hackers who bought the boards and panels off of AliExpress and did DIY monitors. I think that it was more the nature of Apple’s relationship with LG that prevented them or at least highly disincentivized them from offering these or a separate 5K monitor. The question now is whether that relationship now compels them to shut down the line for these panels or whether it was repurposed for the new panel in the Studio display. If it wasn’t repurposed and they’re free to do so, it’s reasonable to see either the UltraFine 5K or some variant of it continue. LG has a lot of monitors in its lineup for a variety of niche use cases - they have nowhere close to the product segmentation discipline that Apple does and if it appears like they do, it's much more likely that's imposed by their OEM customers.
I don't think it is the relationship as much as Covid supply chain disruptions coupled to a spike in display panel technological change.
First, are there going to be enough "spare , unused" production equipment lying around to crank up a new 600nit production line for the Studio display. Apple killing iMac 27" and external monitor at same time is somewhat suggestive that it is a "reuse". That very likely the cheapest path to a the Studio Display panels at a price point that Apple is probably demanding. (Apple tells LG , " just use that equipment you have to make this new panel and don't charge us for new capital costs". Likely asking for 600nit panels at 500nit panel prices from a couple of years ago. )
If it turns out Apple can't sell enough Studio Displays to keep a major subset of the production lines occupied, then maybe. However, if Apple is consuming them at an expected pace then that "disincentivized threat" is still in play. Would need to turn into "hey Apple it would save you money indirectly if you let us do x with the glut of panels lying around".
It will be a while before Apple/LG knows what the longer term steady state run rate is going to be on these. But LG is woring on OLED and min-LED displays also. In 2023-24 there is probably be pricing pressure to push a LG offering down. I'm not sure they will want to keep all the 5K production floor space they have assigned to 5K in past years assigned to older tech at that size. ( more 4K stuff. If LG has the 24" iMac that seems a better target to do if going to iterate to a bit lower priced monitor. )
