When you have a team of engineers, this means your entire team needs to either learn or lean on an expert when tougher situations arise.
All the type system does is make that implicit knowledge explicit, and a long the way, stops you from doing things that are likely to cause issues.
It would be unfair to consider your team incompetent just because they are experts with another set of tools. It’s also unreasonable to expect these things to be quickly learned (TypeScript types are not friendly). But I think it’s reasonable to explain the benefits of this approach and to help your ramp up and learn the skill.
But, anyway, I understand the frustration. I’m usually the one trying to get my team to understand the value of modeling problems in type systems.
Is there really that much legwork otherwise? Adding ": string" to a function parameter assumes they know what a string is (which should already be the case), adding an object type assumes knowing what an object is, etc.
Simply adding types is usually not too difficult and it is still quite beneficial. It does eliminate certain kinds of bugs.
Modeling your application in a type system means making invalid states unrepresentable and being as precise as possible. This is a lot more work, but again is eliminates more kinds of bugs that can occur.
An example of this being complex: earlier this week I wrote a generic React component that allows users to define which columns of a table are sortable. I wanted to prevent any invalid configurations from being passed in. This is what it looks like: https://tinyurl.com/bdh6xbp6
It's a bit complex but the compiler can guarantee that you're using the component correctly. This is more important and useful when it comes to business logic.