I'm gonna block quote you but don't freak out.
I don't like to do this sort of thing (long block quote dissections of other people's words, I consider them a sort of Web STD), but I value your understanding of Shaolin concepts (regardless of what you've trained so far), so I'm trying to educate you and everyone else further, because trust me, almost everything I know about Shaolin I learned from training for real, and fact checking with actual research by scientists, including peer reviewed journals. I've done a lot of homework like you have, I just don't make videos.
Let's begin!
The whole of the country is covered in Shaolin lore. Shaolin was hugely famous and influential, certainly not denying that. I'm just saying that it is unlikely there is a direct link between what is commonly seen as southern Shaolin styles and Northern ones. That doesn't make it any less valid, or real. Things in Northern Shaolin came from elsewhere as well as being "home grown", and any practices they have almost certainly didn't come from Bodhidharma.
It's more complicated than even that, but there are many direct links in the form of individual people, what they trained, and what they became known for in history (vs. legend). The Chan tradition is not wholly separate from what most probably learned as "Northern Shaolin", and it's what I actually study/live/breathe. So when you say "practices" didn't come from Bodhidharma, that's a tough sell for me. I have entire books devoted to Bodhidharma scriptures, those inform my actual kung fu training, not limited to Shaolin stuff.
He was, though, retroactively associated with the temple many, many years after his death. The Shaolin were known to do this often. In the same way, certain weapons associated with Buddhism became the iconic Shaolin staff methods (which I also study, because there are few things more authentic).
One funny thing about Kung Fu in general, is that some of the people weren't real, might have been real, or were definitely real. This is also a problem with historical science, eh? Yet someone these transmissions reach us even in the 22nd century.
Pretty much all of the commonly accepted history of Shaolin is fake beyond the broadest of brush strokes when you actually get down to the real records, but these being myths doesn't invalidate the art.
"common" means the man on the street. So what they say about Shaolin, who cares. These are the same people late night talk show hosts flame on the streets because they answer "Canada" to questions like "What was the 50th state"?
A lot of what the common person believes about Shaolin is actually true (e.g., they have badass athletic skills, they fought in battles, the temple was an epicenter of Daoist and Buddhist martial arts, etc).
If you read any scholar (historian, etc) on Shaolin-based martial arts (Mahar, etc.) you'll find the same themes, and that a lot of the craziest sounding stuff is true.
The first half of this video talks about Shaolin lore in southern styles-
I'll watch the video for sure, but it might need its own thread. A lot of Youtube videos are full of BS, especially kung fu ones. You know it
I'm sure you'll agree, you have to do your own homework with this topic!
The same stances appear in a lot of styles, and the whole animal thing is massively over played with Northern Shaolin these days. Animal iconography is used to name some techniques and postures, but the whole crane, snake, monkey, leopard etc. styles, it's all just modern performance stuff. Old Northern Shaolin is not animal imitating at all. You see some forms called tiger something, but they are not imitating tigers. There's Monkey Rooster and Snake Qi Xing Quan too, but again they aren't specifically imitating these animals.
This part is not true. There is about 1500 years of Shaolin writing, the animals are all in there, dude. SO are the Wu Xing elements. It's all tied into TCM, too.
You might have discovered one of the major issues with the entire process of trying to learn Shaolin kung fu. It's NOT just about hitting things.
China has a long history with much movement of people. As such there are many shared cultural ideas and so you see similar things popping up all over the place in terms of naming.
But all that is the doctor of Archaeology talking. Ultimately it doesn't matter what any style is called, where it comes from, how it names things or anything, all that matters is that you have fun training it and it delivers what you are looking for out of a martial art, so I'll go shut up!
I see you, dude.
This is more a matter of anthropology. And according to Chan itself (or Daoism for that matteR) there is no "northern" or "southern" shaolin. It's all one diaspora, like the lotus flower (see: the Buddha)
Look into Leung Kwan, one of the most important Shaolin martial arts figures of the last 200 years. Wasn't even an ordained monk. Apparently once, he bumped into a kid and taught him all sorts of Shaolin technique that he himself had been given by hanging out with all sorts of Buddhist monks his whole life. That kid became, arguably, China's greatest martial arts hero. And it wasn't Ip Man.