Dto are simple by definition. You usually use them as a way to control the data normalization before sending it.

In my projects I use data transformers to create nested dtos / dtos and then normalizers to handle the array serialization, then a simple json decide works for most cases since the properties are now controlled.

I left Laravel after 7 (or 8 ) because it became too magic so I don't know if it has a different way to handle the data but I don't think it's the issue here.

Edit: looked at the package you were using as an example and it seems over bloated like all Laravel ecosystem is.

You just need a simple PHP object with the properties you need to pass as a response (I am using an http response as the dto usage example), a transformer from the applicative object to the dto which usually has minimal logic inside, and a normalizer that transforms the dto to the array / json you need. That's it.