Elder Scrolls 6 is pretty easy to explain, they simply were not working on it, focused entirely on Starfield. That teaser from years ago was a distraction to make you think they were still working on it, and to get shareholders to shut up about them not putting out the next installment.

Big Boss practicing CQC circa 1964

"The enemy soldiers became distraught at the number of their dead and wounded and began screaming and wailing."