At this point, I've stopped posting rumors from the various hokum merchants, because the rumors have become so inaccurate. Gurman was exposed at WWDC, a month before he swore that the Mac Studio wouldn't be updated until much later, and the Mac Pro wouldn't get an update until later this year. He scrambled a few days before WWDC to backtrack on the Mac Studio, but even then he was noncommittal and was likely basing his assumptions on developer logs. He completely botched the Mac Pro, there's no way for him to weasel his way out of that. It's clear that he burned his best sources long ago and now is subsisting off of scraps, hoping that his previous reputation is enough to sustain him going forward. Plus, I think he uses being a Forbes reporter as a shield; would folks pay him as much respect if he didn't work for an ostensibly reputable news organization?
Gurman's most recent rumor is that there will be a 32-inch iMac coming in late 2024 or sometime in 2025. We've been hearing rumors of a larger iMac since the announcement of Apple Silicon, and thus far there's been nothing. Hypothetically, I assume this would be a way to extend the useful lifespan of the current XDR panels, so at least there's some logic to this notion.
Other rumormongers have either dropped off the map, or much like Kuo, lost the plot long ago. Even display analyst Ross Young, who I don't think is peddling nonsense sourced from his scrying pool, has missed the mark recently. He admitted that he botched the Apple Studio Display, thinking it was a new iMac. He's been chatting about a 27-inch mini-LED Apple monitor for some time now, which has yet to make an appearance.
Sure, Apple prototypes a lot of devices that will never become products, but it's become easy for them to hide behind "plans change" and move on to the next shiny thing, hoping that we forget about past botches.
I don't think there are any reliable Apple sources any longer. The fruit company has clearly done a good job on clamping down on leakers. This is good for Apple and good for "surprise and delight" when they make announcements. It's bad for those of us who are looking to make a purchase in the near future, as I've stated before I need both a new Mac and a monitor to go alongside it, but I fully understand that basing purchasing decisions on rumors rather than actual need is not a good strategy.