There is certainly some value in having all the wrenches in one drawer, but in this case, wrenches from different manufactures might have the exact same name, but function differently (especially when you get to higher-level functions). There is also value in knowing the manufacturer. If there is a XOD builtin that does what you need, there is no reason to use the off-brand copy that is more likely to break.
Why clutter your main drawers with tools you never use? The library system was never intended to download the entire library & see if there is something you might be able to use someday. It is intended as a resource to search if what you want is not builtin before you run off to build it yourself. There might be 3 implementations for a single device or function. If you don’t know what you might do with it, it will be hard to determine which is more appropriate, but you are not likely to need/want all 3. It doesn’t make much sense to download what is available now in case you might need it in the future, since what you need in the future might get added after you do the downloads (or there may just be an update for what you downloaded that will avoid a lot of aggravation trying to get it working).
Did you go through the built-in tutorial showing basic nodes and how they work together? It creates working patches that you can upload to your Arduino without any additional packages. It seems odd that someone would complain that instructions didn’t include what you don’t need to do…
BTW: modulo and divide are two different things (modulo returning only the remainder of a divide operation). I have never seen a programming language that used add-string instead of concat, but if you search for “add string”, it finds concat because both those words are in the description.
The built-in nodes give you easy access to low-level resources of Arduinos. You need to have some knowledge of gates/ports/etc. to use them. They are able to hide some details (like initializing input/output pins), but you reduce their usefulness if you abstract out too much. There are some wrapper nodes for specific functionality that is able to hide some of the options/complexities of the low-level nodes. Many libraries are able to abstract out all of the details and just provide a specific high-level function, but you are likely to need at least some low-level nodes to tie everything together.
The introductory tutorial gives you the basic building blocks and and getting started with XOD, then lets you use your imagination of how the parts might be used together. The best way to get started is probably to make small modifications to the examples and combine some together. Jumping straight to “this is what I want to do” is probably going to be too much to get started with, especially if you have never done any programming.
If you want an example of trying to explain why things were done the way they were, you can take a look at gweimer/traffic-light-advanced which tries to explain how pulses can be used to control program flow (and throws in some ideas about encapsulating functionality into a node), but any attempt to explain why is going to be a balancing act between being condescending about stating the obvious and taking someone on a torturous ride through your own thought processes… (My tutorial probably errors on the side of torturous ride…). It also assumes you have been through the basic tutorials and have a general understanding of XOD and tries not to dwell on the obvious (and probably misses some things that are not all that obvious; especially for beginners).
Unfortunately, almost all of the early contributors generating libraries and tutorials are going to be people with programming experience. It can be difficult for us to pull back from all that experience and speak to “normal” people. We do our best to answer questions when they come up.
Unfortunately, not everyone is going to be able to program, no matter how simple we make it. That is not an insult…some people just think/work differently. Computers have a tendency to do EXACTLY what you tell them to do, instead of what you meant them to do (hence the joke about the programmer who died in the shower. The shampoo said lather, rinse, repeat…there is no stop condition so he kept repeating). The creativity and impulsiveness that makes someone a great artist is going to work against them sitting down and systematically breaking a final goal into small tasks that can be easily programmed. Some outgoing people persons who are great at working with and motivating others are not going to want to sit down at a computer and drag icons around and link them together with wires. Something like XOD brings programming within reach of a lot of people who could never program in C++, but it is not going to work for everyone. I do NOT say this to suggest you should not be programming, just pointing out that there is a whole spectrum of people XOD is trying to reach. It is pretty much impossible to reach them all in a single tutorial. Maybe we need to focus more on trying to write a few non-programmer tutorials to help get newbies started, but that is very hard to do when you have no idea where they are coming from. There will be some who will never get it, some who will need one-on-one help to get started, some who just need a little more than what is provided to get jump-started, and some who feel what we have is all that is needed.