I think this is rather an expansion of how you view the world. It's a language that does indeed force you to simplify things. Using Toki Pona as a universal language, that fulfills the function of being used to write laws and such is probably not quite the most thankful idea. But virtually every language comes with concepts, another language does not have. Toki Pona in some view might be a constructed antithesis to the natural German language. Useful for law and science? Probably not. An interesting way to broaden your knowledge about philosophy, the way languages work and such: I think it definitely is!
Fun fact: Without looking on my vocabulary list, I think I can make up words for both "Dichter" and "Denker": jan pi lipu musi (A person of funny documents) and jan sona (A person of knowledge/thinking).
And here comes my thesis: Toki Pona can be more precise than German. When you say "Dichter", you have a broad category in mind. When I say "jan pi lipu musi" I have a person in mind, that writes funny texts. Not all poets write entertaining/funny poetry, though. Entertaining poetry is a certain genre of poetry that I am forced by the nature of the language to specify - for you, specification is something optional.
Edit: Learning a new language - including, if not precisely Toki Pona - is like adding a sports car to your collection of vehicles currently limited to an off-road vehicle