Seeing my kid create strong passwords without my help was a proud moment!
My son used to use easy passwords like his birthday for everything. We talked about how hackers can guess those. Now he makes up fun phrases with numbers and symbols. He showed me his new password for his game account today. I feel like our home is a bit safer now.
Actually strong passwords are still mostly security theater for normal people. Most accounts get hacked through data breaches at companies, not guessing someones password. The real hassle is remembering all those complicated codes or dealing with a password manager that locks you out. Lets be honest, most folks just use a simple variation of the same password everywhere because it works fine. The odds of a random person targeting your specific account are tiny.
Did you use any tricks to help him remember those phrases? With my niece, we turned passwords into silly stories about her favorite cartoon, and now she recalls them easily. That kind of fun practice makes the good habits last, so you've really done something great here.