Denos approach is super cool, but it is so hard to transfer simple things from node to deno.
First, a disclaimer - I'm not completely certain what DTO's are, or even Reflection in this context, just a hunch. But anyway:
Looking at your two open posts, they don't look particularly simple transfers though. Reflection and GYP related things seem to me like pretty involved stuff that are heavily linked with node internals.
Deno's node compatibility is great as long as you are dealing with relatively straightforward javascript libraries.
But when you (or the libraries or frameworks you use) start fiddling with native code, reflection, custom module loaders and other stuff meddling with node internals like that you are bound to run into problems. I don't even comment on the added complexity or potential for interoperability bugs typescript brings to the table.
Many NPM modules do really weird node-specific stuff, and it could be asked, if one actually need that stuff, maybe one should the real thing (node) then. Because there are limits how far Deno can, or maybe even should take the node compatibility.
It's like, people seem to have a lot of problems with Deno and Vite - and Vite to me seem like exactly the type of system that does a lot of unorthodox things under the hood, or assumes a lot of things are implemented in a particular way to make the magic happen. This makes 100% compatibility a very much non-trivial thing to accomplish.
Sorry if this is not much help! Just an observation! The types of questions you asked, I'm not that surprised no one has been able to give easy answers, is all. Not sure if there are any better channels to ask. Folks tend to be pretty helpful here at least when the questions can be answered with relatively little effort or the solutions are "common knowledge"!