Yeah, I doubt it, and I certainly would hope not. IMO they don’t look that good. Given the lack of any credible sources actually within Apple indicating they’ll switch to circle icons, I don’t think that’s happening. The squircle icon has been a defining aspect of Apple’s visual branding for the past decade, IMO, it would be as likely as Apple switching to block shaped iPhones with hard corners. Apple won’t want to completely remove any vestige of familiarity with the new design language, the new design language should build on the existing design, retaining an element of familiarity and consistency, while also incorporating some new elements. So I doubt they’re going to do that.
I could see circle icons and symbols within apps, but I don’t believe circle Home Screen icons would make any sense. For one, app icons coexist on the Home Screen alongside rectangular and square widgets, and possibly folders and files as well according to rumors. None of these visual elements would likely be circular. So you would have circle icons mashed together with square and rectangular elements, which would look way too chaotic and imbalanced in my opinion. Then you also have the issue of app branding. Many apps utilize the squircle shape as an integral part of the icon design, to represent real-world objects. Many such apps would have to completely rework their icons, which could be harmful to brand recognition. Squircle icons afford more creativity, devs can use the shape of the icon itself as an aspect of the design, a squircle shape lends itself to representing a whole bunch of different real-world objects. A circle shape, not as much…
I’m guessing the app icons will look more comparable to the 3-dimensional macOS app icons, with more depth shading and layered icons. The designs of the icons may be different from the current designs, but I suspect many of the design principles we see in current macOS app icons will likely be there…
In fact, I suspect that Apple has been using macOS as a testbed the past few years to tinker with some of the visual elements that will wind up in the new design language. We already see pretty widespread use of “frosted glass” UI elements in macOS. We also already see 3-dimensional elements like the aforementioned app icons. I’m sure the new design language will likely look a bit different from current macOS UI, but I suspect we can already see many hints of it in macOS.
At the end of the day, I hope Apple will retain squircle icons. Traditionally, Apple has shown close care to visual branding and beyond just that, matching the software aesthetic with the hardware aesthetic. In my opinion circle icons would be a major departure from that, and would hurt Apple’s visual branding.