Composer not evaluated on partial view called by a component inside a block

Hi, here’s an issue that’s giving me headaches since a couple of days.
I have a block which contains a component and that component includes a partial like this:

@includeFirst(['partials.content-' . get_post_type(), 'partials.content'])

I have also a composer in Composers/Product.php with

protected static $views = [

The issue is that when the block is rendered, I don’t have any of the with() variables instantiated inside my partial/content-product.php and I can’t understand why.
Of course the setup_postdata() is correctly called before the include, and WP functions (get_the_ID(), get_field(), etc.) work fine.

What am I doing wrong?

PS: the need for the block > component structure is to make a single component reusable either as a block (to use in WP editor) and as a component (to use in templates).