Maybe then question then is how does one get every developer to design and build modules as you have prescribed? (Recognizing different talent levels across the industry / delivery deadlines). Genuinely curious to know a scalable solution for this.

edit: typo

Agree with this. Ppl can make a mess inside their typesystem specs esp. when making their code interface with others on a large project. Adhoc types that are just bloat. Etc.

Has anyone else had multiple years of experience with typescript in prod or what?

TBH, I feel like the TypeScript movement is driven mostly by junior developers. The software industry has always been like this; young, loud-mouthed junior devs come in thinking that they know better than all the senior people... They ridicule their elders who have an actual proven track record; they then proceed to push their naive ideas on the entire industry... 10 years later they (sometimes) realize how dumb they were (yes, I've been there myself) but by that point, the next, bigger batch of loud junior devs enter the workplace with even dumber ideas and drown out all the wisdom yet again... Again, the juniors with big egos, fresh out of MIT, think they know better than all the old dinosaurs and they perpetually keep destroying every chance of actually moving the industry forward... The cycle repeats over and over.

I agree in general except what you said about MIT ppl. I find them to be the humble ones, ironically.