It's only the most difficult path if they want you to read these books - but they don't. That's why what the books have established for where Bruce attended school doesn't matter - that's all in continuity, a continuity that we hardcore fans may know, but not the demographic of these books. Comic book fans are largely an older and aging demographic, DC wants to attract new and younger demographics to sustain them once many of their current fans start slowly dying off of old age (not calling anyone here old, much less near death, just stating some broad facts). So to attract new readers they want to try new things, new plots, genres, styles, new continuities, and so on. A whole Elseworlds type multiverse focused on the sorts of stories teens and preteens read and watch. So we get things like teen Bruce and even teen Batman, Bruce going to school and having school life drama with Selina and Joker. Stuff that isn't in continuity, isn't like the stuff we know, are used to, or want, but might draw in a crowd DC isn't currently drawing in.
Now whether or not they are right or succeed is a different argument, but it's certainly not the most difficult path in trying to expand their audience - that path would be to not even try and do nothing different.
By the way, not singling you out or anything, just saw a way to kind of come in with this thought. A lot of people think if they aren't interested or it's too different from what they're used to it has no value, but from a different perspective it makes sense. DC already has our dollars and is continuing to make books we will buy, this is just an attempt to get some different people's money.