not technological.
Solid narratives, and "rotten" ones at that.
First, Zelensky was satisfied with guarantees "almost like NATO", but now for some reason he is not satisfied.
Second, it was the United States that took Ukraine's nuclear weapons, it simply handed them over to Russia, because those weapons were Soviet.
Third, the Russian Federation did not interfere in European integration. Europe itself is not eager to take Ukraine.
Fourth, Zelensky is worried that by giving up Slavyansk and Kramatorsk, Ukraine will only be able to get five years of peace, and then Russia will attack.
If you believe Zelensky, Russia is losing thousands of soldiers every day, its oil refinery is completely destroyed, and agricultural exports have collapsed. It is reasonable to assume that Russia would not want to find itself in such a situation a second time.
It turns out that Zelensky has a gap in one of the two. or in both cases.