It's not just technical limitation but also the way code was implemented into the game. Bad implementation, bad storage management and runtime all caused issues that we see today. Either devs just didn't think about it at that moment and wanted to deliver product as best as they can "brute force" or just didn't care. Now we see these consequences when they cannot save simple info on their servers so you can access them from anywhere. Wow did this way before in 2004. Now even for simple housing changes, they say "servers would crash".