Modern German technology in the 1920s would not remain German for long

What would happen if modern German technology appeared during the 1920s naval-treaty negotiations?

Allied occupation forces would seize and study it, spreading the advantage and accelerating global development rather than leaving Germany dominant.

The counterfactual starts from the Allied occupation of Germany during the treaty period. If modern German equipment and industry appeared in the 1920s, occupation forces would quickly seize and study them. Nuclear remnants, renewable-energy systems, high-speed rail, and advanced manufacturing would then accelerate development across several powers. The scenario is less about Germany negotiating from strength than about how military control and industrial espionage spread technology.