Lenin was never interested in worker control of means of production.

Trotsky was just a bloodthirsty bootlicker.

They just wanted to control the revolutionary movement and use it to build their own power. They weren't interested in democracy and actively fought against it.

The Bolsheviks only got a quarter of the votes in the post-1917 election and they did so much election fraud (stuffing the ballots, intimidation etc).

Once they seized power, there wasn't any other way it was going to go than Stalin. It was the natural continuation of the model they created.