The 10x engineer tries to standardize problems and solve them en-masse.
The 1x engineer sees every problem as a different problem that requires a different solution.
The 10x engineer talks about abstractions, the 1x engineer talks about concrete implementations.
The 10x engineer believes in investing in productivity. The 1x engineer wants a visible solution right now.
The 1x engineer never has time because they're too busy making themselves less productive by owning more and more code to maintain. The 10x engineer is always looking for code to remove and refactor, and making the solution as small as possible.
The 10x engineer will talk about programming language features and libraries that promote reusability, the 1x engineer only talks about tangible stuff.
The 1x engineer talks about their car and weekend, the 10x engineer talks about technology.