Microsoft Software is Embarrassing

So my sister bought a new computer for my niece for her to play Roblox and watch educational content and whatnot. I offered to set it up for her and installed a fresh copy of Windows 11 from a USB key. Everything appeared to go smoothly, I created an Outlook account for her, signed in for the first time and set up all the software she needs. Great so far. I reboot the computer after installing the graphics drivers and when I try to sign in again, it says I can't do so without a guardian or parent. Interesting that it let me do it the first time. OK. I enter my sister's email but it errors out again because she's not recognised in the system as being my niece's parent. I go over to Microsoft's support page to find out that there's a Microsoft Family Safety iOS app where my sister can add her daughter to her family. We install the app on her phone but... there's no way to add new family members to it. Despite saying on MS's website to specifically use the app. Fine, I'll just use the web version. That one did have the option to add new family members. I add my niece's email and hit submit and... it errors out with an internal error. "Something happened on our end, here's the trace id, try again in a few minutes." I try again after a while just for lols and it breaks again with 500 status code responses in the Network tab. I try to sign in to my niece's MS account on the web, hoping it will let me add a parent from there, but it gives me the exact same guardian/parent crap. So at this point I'm beginning to think my niece is screwed and I have to install a new copy of Windows to get around this crap. HOWEVER, on the Windows sign in page, I find out there's a way to MODIFY YOUR ACCOUNT INFO, including birth date. I change it to have her birth year as 1980 and it lets me sign in. Yes, any kid can just do this instead of getting their parent's consent, which they might be forced to since Microsoft's family sharing system is completely broken and an absolute joke. I've known Microsoft's software offerings to be vastly below every other big tech company in terms of customer experience, usability, and general functionality, but this is like, unbelievably bad. Why is their software quality so terrible? Do they not test their things or have alarms in place for when something goes wrong? 2 YoE T: C