[omnicognate]

You can see the announcements at https://archlinux.org/. The most recent is from June:

> Starting with libxcrypt 4.4.21, weak password hashes (such as MD5 and SHA1) are no longer accepted for new passwords. Users that still have their passwords stored with a weak hash will be asked to update their password on their next login.If the login just fails (for example from display manager) switch to a virtual terminal (Ctrl-Alt-F2) and log in there once.

I wasn't affected. The next one before that was February, and also didn't affect me.

I think I could count the number of such planned manual interventions that have affected me in the 6 years I've been running Arch on my laptop on the fingers of one hand. It's approximately the number of times I would have had to reinstall my OS from scratch in that time on most other distros, based on extensive prior experience of whole distro version upgrades messing things up in mysterious ways. I put this down to the rolling release and the arch devs not being lulled onto assuming everyone's running a fresh, pristine installation.

I have a 6 year old, heavily used (including for work), heavily customised development laptop I have installed the OS on exactly once, and I have absolutely no reason to contemplate starting again from scratch. It's bang up to date and rock solid. You'd have to pry Arch from my cold, dead fingers.