The current version of Lightroom Classic isn’t even designed for M1 Macs, it’s an Intel version that is only able to run on an M1 Mac through Rosetta translation.
Some fundamental technical aspects of applications like Lightroom Classic are simply not supported on iOS regardless of processor, and Apple does not provide any way to install macOS on an iPad. That’s why the only version that runs on iPad is cloud Lightroom (not Classic) on iPad OS. If anything changes about that, it will depend on Apple expanding what iOS supports. The soonest we might hear about that is if Apple announces sufficiently radical changes to iPad OS (or much less likely, iPad support for running macOS) at Apple WWDC on June 7.
Many people hope that Apple giving the iPad an M1 and up to 16GB RAM indicates some kind of big shift coming in what Apple will let an iPad do, but we won’t know what that is until WWDC.
Yes, and it is interesting to revisit this post months later. Lightroom Classic is now optimized for M1 Apple Silicon, but…in the many months since the M1 iPad Pro was released, Apple WWDC came and went, the release of iOS 15 came and went, and still, Apple has done nothing and announced nothing to make it possible to run Mac software on an M1 iPad Pro. All of the hopeful speculation for Mac software on M1 iPad Pro never came true. So we cannot expect, any time soon, to be able to run the Apple Silicon Mac version of Lightroom Classic on iPad OS without modification.
What’s left, is to wonder how likely it is that Adobe would completely rewrite Lightroom Classic for iPad OS. But that seems very unlikely for now, largely because of the ways that iPad OS does not support everything that macOS does. If Adobe tried to make Lightroom Classic for iPad OS today, under the limitations of iPad OS and the constraints of a touch UX, it would probably look and work at lot like the existing ground-up rewrite of Lightroom for iPad that they already did.