You got it wrong.
Rosetta is the technology that allows Apple Silicon hardware to execute Intel software. When they introduced Apple Silicon with the M1 processor, not many binaries existed for Apple Silicon, so Rosetta2 was a bridge for that problem.
They used the same technology (Rosetta 1) when they switched from PowerPC to Intel.
Pretty much every binary for macOS is distributed as a "Universal Binary", which contains binaries for both x86 and Apple Silicon, so x86 isn't being abandoned, only the ability to run applications on Apple Silicon that hasn't been redistributed / recompiled in 6-7 years.
No, I didn't get it wrong. The moment Apple stops supporting to run x86_64 binaries on ARM (M) CPUs, everyone including Apple will stop making Universal Binaries. Because (among other reasons, like lack of motivation) there will be no easy way to test the x86_64 part of the binary. The Intel MacOS era will be over. Just 5 year after Apple sold the last Intel-based Mac Pro.
Is that really a problem though ?
Unless you’re doing something special, you can be fairly certain that universal binaries will behave well on both platforms, that’s what Apple guarantees. They expose one API, which can be executed on multiple hardware architectures.
If you’re doing something special, like an image editor, or a game, you might need to test performance, but you couldn’t really do that with Rosetta either.
Universal binaries work well. And as long as they exist, apps will most likely run just fine on both Intel hardware and Apple silicon.