Firstly, it is nigh-on impossible to match a definition to a specific version of a dependency. For example, say you were using amcharts, you can grab a version of the definition… but you’ll need to basically be using the latest version of TypeScript and the latest version of the library (because otherwise, you will struggle to find the historic version that matches what you are using). This is a real conundrum, because if you are using an older version of a library along with the latest version of TypeScript, you’re only hope is to find the version of the type definition that matches the version of the library and then update it to the version of the TypeScript language you are using. Painful.
There is no blame on the contributors or co-ordinators of the Defintely Typed project – in order to satisfy all of the possible combinations would require a million branches, which would be no more helpful and impossible to maintain.
But this is the reason that, given the choice, I’d rather consume a library written in TypeScript when I’m writing a TypeScript application. In some cases, this is simply a case of “pasting the library into a .ts file” and handling any compiler warnings – in others it means using a TypeScript alternative when one is available.