Statement about quantity when using the plural without indefinite pronouns?

Hi everyone,

I personally understand the plural without an indefinite pronoun as a kind of generalization or blanket statement. In these cases, it seems to me that one could also include "in general" in the sentence or use the indefinite pronoun "all." However, that's just how I understand it, and it doesn't necessarily correspond to reality. But it's precisely this reality that interests me, preferably with sources… Here's an example:

"Houses have windows and doors." What does this sentence say, objectively speaking?

Thank you very much in advance for all the feedback.