Cloud/DC basics which are bugging me for years

This might seem weird, but still a valid question which I ask myself more often.

I work as a network engineer for decent amount of time and have couple of certifications. And this fact makes me feel shy about asking this question even more. And obviously I can’t address this question to my direct colleagues. The questions is ‘why everything is moving (or already has moved) to the cloud/datacenter?’ and ‘why cloud is so great and cool’. Somehow, I’ve missed the cloud-hysteria and can’t get into the idea now. I work in datacenter environment - with firewalls accepting connections from public Internet, some core routers routing various flows here and there, load balancers and other stuff. I guess it’s rather typical design. But I have no architectural picture of the whole process. I just receive a technical task/trouble ticket – permit that flow, accept these connections, create this server pool and LB in this manner and that’s it.

I tried to watch some free educational videos on Udemy, etc. But all of these are strongly accented on different cloud models (XaaS, where X belongs [A-Z]). But this is not the thing I need. What I need is a high-level explanation of why cloud is so cool and some typical examples of deployment and how an enterprise can benefit from all this process. Any help, explanations or materials and links would be appreciated.

Please no joking like ‘how did you even get your job without understanding such basic things?!’. I've got what I've got and trying to fill this blank space. Thanks.