As the constitution clause states, it's not the goal to have these exclusive rights; these exclusive rights are the means(motivation) by which to facilitate the creation and publication of such works.

You're absolutely right, but what you're saying suggests an even more limited ability of congress. The whole point of the United State's political design was to strictly limit the ability of congress except to what was allowed. For instance the right to free speech does not grant citizens the right to free speech -- that is already inherent. It prohibits the government from being able to take that inherent right away.

The constitution is not a guideline to unlimited powers, but constraints to limited powers. If congress is passing various copyright laws for reasons other than to "promote the progress of science and useful arts" then it would be unconstitutional. In other words passing laws to enhance profits rather than to ensure creator motivation would be unconstitutional, yet that's unambiguously the motivation for nearly all modern copyright law. Nobody is deterred from creating a work because they would only own the rights to it for e.g. 30 years, let alone 110 years.

That's a good point, although unfortunately I could see them getting away with extra power due to the interstate commerce clause that they use to justify so much else.

> Out of curiosity, how many authors and inventors do you think live 110 years after their writing or discovery?

Well now that we've all agreed(lol) that corporations are now citizens, I'd argue that some do indeed 'live' long after the normal squishy citizen(s) that originally invented/created the thing have died (e.g. IBM).

(Note: I agree with your point, just playing devil's advocate)

> So the goal is to enable authors and inventors to have exclusive rights to their respective writings and discoveries

No, that is the means of accomplishing the goal. The goal is "to promote the progress of science and useful arts".