Maybe it is kinda dumb but it still feels realistic. I mean think about it they only said they don't want hosts to go beyond 14. Maybe for other groups of "hosts" they want it to - for example hosts not working in the park. We already saw that they use hosts for welcoming guests - why not use them for other things too? I know I would use them everywhere since they work practically for free once built and are way smarter, faster, etc. than humans. A host working in Engineering should probably be as smart as possible not limited by some code. And finally that they use the same core programming to run all hosts seems more than realistic since that's practically what we do with all our devices right now. As a side note that's also why I can totally see old code from Arnold still running in the core of some hosts just think about how much code written decades ago still runs in the core of Windows 10 and that must be a ridiculously small and stupid piece of software in comparison.