The shape of the color picker is beyond our influence. You’ll have to make some noise about it to the Blender developers.
Also we don’t recommend using 2.8 for following 2.7x tutorials. There’s too big of a difference between them that it will always cause confusion unless the learner is very self-motivated. All of our fundamentals courses will get an overhaul for 2.8. In the meantime I recommend using 2.7 or the specific version used in the tutorials you watch.
