Teach good password hygiene. Use keepassx. Use decentralized third party authentication with providers that know what they are doing and use 2FA and such!
But password restrictions achieve very little. Let people use their 12345 if they really want, they won't learn by watching the stove but by touching it. Some people are like that and we should educate, not babysit.
There are many sites which contain none of my personal info but I have to setup an account just to view website content. If my account gets hijacked, it might be used for spamming. But still If I could make a throwaway account with a blank password I would because I don't care about that accounts security. So surely some restrictions need to be in place if you're going to require signups.