To note, almost all programs are the same way and miles will expire without notifying you about the expirations.

It is your job to keep track of the expiration dates, not the airlines. There are also plenty of ways you could have kept the miles from expiring without actually flying.

So if it angers you and you will not fly with them because of it, be prepared to not be flying much anymore since you will have the same result with the vast majority of carriers.