So, it's just more safety that protects you in the end. I agree the reg key was easier, but on the plus side, since the keys are now tied per computer, there's no way people can get ahold of your regkey and mass distribute it, especially since it is required to log into your account (and if you use 2fa, nobody will be able to get in for sure). No need for online at all (just a slightly more complex activation that's all). You only need to initially generate a file on the offline computer, log into your account online to generate the code, then take it back to the offline computer and activate it. You can use it with an offline computer just fine.
