Well that's the thing. I don't substantively see any stances have been removed, when you compare Shotokan kata to TSD hyung. The Koreans do that foot-raised thing on their back stance, almost so it functions like a cat stance, but the embryonic purpose of zenkutsu-dachi, kokutsu-dachi, and kiba-dachi are all there in the beginner forms.
If you're referring to practicing forms with purpose, I'd agree that Wado and Tang Soo Do people probably have very different ideas about what the kata is teaching. Any points made about complexity lost or gained probably fall into this bucket rather than the pure physical choreography itself, as different though valid interpretations can be drawn from the Korean alterations if one is so minded.
I don't know Shotokan katas though so I'm afraid I can't compare them, (perhaps Shotokan have also taken them out?) Mine are Wado Ryu. The stances taken out of TSD are Nekiashi, Sanchin, Seishan, Naihanchi, Zenkutsu, Chidora, Cyakuzuki and Kokutsu. those are just off the top of my head. I know we have far more stances as a whole in Wado than most other styles.