Parameter properties are I think still used quite heavily in Angular, but I don't see them much elsewhere. Again, they're a very old feature, and they don't play well with newer developments in the language (such as native private attributes), so it doesn't seem like much of a problem to avoid them as well.
The other big TS-only feature is old-style decorators, but that shows the danger of relying too much on this TS-based syntax sugar. Decorators have gone through several revisions, and the version that Typescript implemented is long dead. But a number of codebases are still stuck using this legacy system because it's not compatible with the newer versions of decorators that will (eventually, hopefully) be implemented in browsers. The legacy system is still maintained, I believe, and you can still keep on using it, but you'll not get the benefits of using the same system as the wider Javascript ecosystem, and you'll not get the benefits of having the syntax be native to browsers, when that happens.
In general, Typescript works best when you use it as simply a type annotation syntax for Javascript, and not as an additional layer of sugar on top of that. And clearly the Typescript developers see things similarly, because they've stopped implementing sugar-like features and have committed to only implementing the stuff that will also be implemented as new features in Javascript.