They are not more simple; they think concretely, which is not the same thing. NTs and NFs just think in abstractions.
Guardians and Artisans are concerned with what was and is. Si and Se are focused on experiences, their own and others', respectively. The SJs are concerned about tradition and preserving the status quo; SPs want to test the rules and push the boundaries. There's more, but that's the gist. Again, this doesn't mean that they're "simple".
The intuitives are more concerned with what they want and what's possible; Ne is focused on the wants and possibilities of others and Ni is focused on the same, but for themselves. Again, these are the basics. Every type has something to offer and they all deserve respect.
And that is totally an INTJ lecture. Sorry. I'm not good at doing it any other way.
The only SJ I've ever known was my grandfather and this fit him to a "T." He was very quiet and even tempered. I rarely saw him angry but when he was it was always over the tiniest things and those were abstract concepts or non-traditional methods. They seemed to confound and agitate him to an absurd degree of "Can't even."
He was supportive of my artistic hobbies but whenever he saw me drawing but was aggravated by the subjects and every time would say " Why don't ya draw sumthin real? Like a mountain or a cayote howlin at the moon?"
Or when he watched me playing a video he would comment " Why're they jumpin so high!? No one jumps that high!" you know, despite every other ridiculous thing in the game.
The angriest he ever got at me was one day when I was gong to...I don't recall school, or some appointment. i didn't have everything organize and planned out perfectly and when he asked me about it I told him " Eh, I'll figure it out as I go." This flustered him.
" That's not how things work."
"That's how I work. I'll nail it, watch me."
he turned bright, cherry red and in a voice that I think was his equivalent to yelling said " No one works like that!"
I tried so many times in my life to explain to him that yes, some people are adaptable, some can-and in fact do better- at thinking on our feet. Every time the concept enraged him and more than once he implied there was something mentally wrong with me.
I don't believe most SJ's are that extreme though. My Grandfather was raised by by emotionally stunted old cowboy so that probably exacerbated things.