When it comes to the iMac, Apple's focus has shifted to the M4 iMac. At the current time, the M4 iMac comes in one size option, 24-inch, and an array of "fresh shades" of Blue, Green, Pink ...
After Apple updated the 24-inch iMac with M3 it seemed unlikely that other all-in-ones were coming anytime soon. Apple confirmed this by stating there wasn't a 27-inch iMac in production.