That video is a terrible example.
A great example of a shader, though this is MC JRE edition exclusive as far as I know, is the Sildurs Vibrant shaders.
I mean, just go to the topic and look at the screenshots of it:
Combined with an ultrarealism texture pack a great shader like Sildurs Vibrant can look like the Promised Land, Elysium, or whatever other terms that can describe something of that decibel.
On my laptop, with its GTX 950M 2GB, 8GB of DDR3/5GB allocated, and I7-5500U, I can run the Sildurs Vibrant Extreme+Volumetric Lighting 1.161 at default shader settings, 16 render distance, a 128x resource pack, and 1080P and I can get 25-30 fps rock solid.Higher if I tone it down to 720P.
Shaders are amazing, and that video cannot represent them well at all.
Why did I just rant about a video on a random thread I found while searching out of curiosity? I have no idea.
Here are my own screenshots of it in MC JRE 1.11.2, showing different places where different features of the shader really shine.
I'm using the VanillaBDCraft 128x textures with it if you want to know.