I'd expect most things to work and have native versions by next year, with the notable exceptions of virtualization software and package managers like Homebrew.
Virtualization software likely will never be fixed if you expect an x86 guests to work. The hardware obviously cannot natively virtualize x86, nor can Rosetta cannot emulate privileged x86 code. x86 Docker images will also not work.
Homebrew itself will probably be ported to ARM by then. However, there will likely be a long tail of packages that won't have ARM builds for some time.
Virtualization not working will require a big change of habits, at least for me. On my current macbook, all the compatibility issues of needing a particular piece of weird software for some client project have been easily solvable by keeping a bunch of VMs with various Windows and Linux versions. You don't want to pollute your host with various short-lived installations of different (often incompatible) versions of various tools anyway, having separate virtual environments (with revertable snapshots!) for separate tool needs is quite convenient.
Hopefully we'll have ARM versions of Linux working as virtualization guests on Apple hardware soon, but losing Windows compatibility will be a pain for me, it will require either ignoring the new Mac hardware, or keeping a separate Windows laptop, which is a pain.
Perhaps having a remotely accessible cloud Windows machine will be the way to go; last time I tried it, it was a pain to use the GUI remotely doe to stutter but perhaps now neworks and machines are faster and this might work better.
Virtualization software likely will never be fixed if you expect an x86 guests to work. The hardware obviously cannot natively virtualize x86, nor can Rosetta cannot emulate privileged x86 code. x86 Docker images will also not work.
Homebrew itself will probably be ported to ARM by then. However, there will likely be a long tail of packages that won't have ARM builds for some time.