In my opinion there are enough easy-to-follow guides for local installation, cloud installation or even docker-setup.
In your case you'll need the local installation guide for windows (I guess you're using windows because of your putty comment).
I agree that the windows-guide is a difficult one to follow since windows doesn't have anything to make your life more easy (like a well-working package-manager, etc.).
But your conclusion of missing guides on NodeBBs side is the wrong direction. You should expect of your OS to give you some hints on how to install software on it.
You simply cannot expect of a software to describe how to install it under all circumstances.
And windows is NOT the most-used OS for web-services. It's just (sadly) one of the most used OS in personal area and surely not optimized for development, network-connections or web-hosting.
Did you expect of your php-scripts to explain how to install them on any OS with any php-environment? Should any php-script come with an explanation how to install apache/lampp/xampp/whatever on any OS?
The only valid reason (from my point of view) for NodeBB itself to keep and manage those installation guides is because it's distributed as a git-repository and has a few dependencies that need to get installed additionally. And this is the most important part of the links above.
But you won't see any non-single-line description how to install those dependencies since it's not within NodeBBs responsibility (and capability since the installation-guide would need to keep up-to-date).
You don't need to run Windows for NodeBB (and I'd highly disadvise) but if you're using Windows you shouldn't expect of a software to describe its own installation as far as it's the default way of installing software.
If you want to use a cloud-service to run your NodeBB you shouldn't expect NodeBB to explain how to use that cloud-service or connect to it from any OS. It's a task of the cloud-service to give you a short introduction how to get a running connection. And even those shouldn't need to explain how to install putty on windows.
Hence that NodeBB delivers some guides on how to connect to a few well-known cloud-services is an overhead that doesn't need to be, it's an additional service of the NodeBB devs/community. But "Real need for better docs for noobs" should be out of question. You should assume that anyone who uses an OS should be "proficient with the system". If they're not they need to learn how to use their favorite search-engine or switch to another system that's more comfortable (and most likely doesn't cost anything ).
In my opinion NodeBB should even have less docs about installation since I don't want users without any clue what they're doing to setup an online service.
This privilege should be dedicated to those who have learned to understand what they're doing since it comes with a great responsibility and a bunch of work (that isn't any-near done after the setup) to run an online service.
To run an easy-to-setup platform like NodeBB doesn't take the responsibility of you to be aware of internet-policy, copyright laws or worst-case-scenarios.
So all in all my opinion contains that "noobs" shouldn't think about running a platform at all before getting familiar with the system and the platform.
But don't take this as an overall opinion of the NodeBB-community, it's my personal one and I expect a broad pool of (different) opinions about that to be present here
I should really learn how to write short answers and how to not make a discussion about windows vs linux within each post xD