oh.. so you lied to me. So realistically, the superior technicians still experience some tension.
guess magic isn't real. I do not believe anymore, now all the realms of story will be destroyed forever, and I have burned the book of fairy tales in front of the dark fairy(OUAT)
Yes, I lied to you with malicious intent.
Just joking

. Realistically we all experience the occasional sensation of anxiety, get self conscious for a second on stage, have an "oh sh*t, where am I supposed to go next" moment, or just a small fumble of some kind, which results in the tightening of some muscles or whatnot. The difference is that with a refined technique you strive back to the freedom and suppleness of everything, learn to release these things as they happen, instead of letting "tension build up as you play". The basic movement of pressing down a key with your finger should not start building up tension if the arm remains perfectly free. Then you just do lots of these movements very fast, without tightening any other muscles and voilá, technique!

I have never understood the whole, hips and shoulders and weird wrist alignments and weird everything that is taught with technique.. I just don't see it. But its been a good 7 years since I last received instruction. I was young. But I guess 8 year olds are doing so maybe that's not an excuse. is it me? Am I the one who is destroying piano technique? 
No, I agree with you. I think people tend to conflate ergonomic playing with raw mechanical ability when discussing technique. Sure, ergonomic playing is important, especially as one gets older, but it's not the same ting. If you want to play faster scales, adjusting your chair and thiking about your hip isn't going to help you at all haha.
If you are locked around your hips, then yes it does. Here's the logic:
We all know that in a highly refined technique we need to keep the arms relaxed, loose, free, supple, free from tension, call it what you will, while pressing down and holding down the keys. This is because any tension, ie locking and blocking any joint from moving freely in any direction of its range of movement by keeping a muscle tense instead of relaxed, hinders both speed and control and security, and if bad enough, builds up fatigue (when I started playing, my arms felt like they were going to fall off after playing the moonlight sonata third movement!).
To keep our arms supple and free, we must also allow our shoulders to be free, because anatomically our shoulders are a part of the arm, and tension in the shoulders prevents the upper arm from moving freely and assisting our fingers. We have a lot of muscles that control the shoulders and upper arm in various ways, that attach to our chest, neck, back, and also to our hips. If our hips are locked instead of free, some of these muscles become locked, or at least less than free. (and if the hips are locked, it's likely that other parts, like the neck, also are, which doesn't help either)
While it's still possible to play just having well trained fingers with these types of tension, it makes it harder and gives less control.
I've talked to some extremely high level classical pianists about the no-tension thing, and they pretty much say the same thing as this post.
And I have talked to high level classical pianists who say playing should feel effortless, feel good, and I agree with them. If I'm working on some loud Liszt stuff and my arms feel tight or fatigued I know I'm not practising correctly. Chords are possible to play with supple wrists.
Here is a description of the type of effortlessness I mean:
https://www.lister-sinkinstitute.org/faq_8.htmlSorry for the long post guys, but I think this is a subject which is very important to discuss.