I think I wasn't as circumspect in my reply to you as I intended. Again, as conceded, there's lots excellent of free verse poetry. As a form, it is neither better nor worse than poetry with rhyme, meter, or other constraints.
But constraints help in aggregate and on average, they work probabilistically like everything in social science. Too much creative freedom, on average, leads to more defaulting to cliches, just like too many options will, on average, lead to more analysis paralysis and suboptimal choices. It's the
paradox of choice problem.
The constraints are for helping somebody who is not E.E. Cummings, Sylvia Plath, Walt Whitman, or T.S. Elliot be more creative. Keep in mind that, by virtue of you having heard of them, those poets are outliers far from the average. My "Forcing someone to write a 5/7/5 haiku... is going to help them produce a more beautiful work" comment refers to plebs, such as myself, who are not proficient writers of elegant verse.
...but I think you and I may have digressed too far from the topic of elfgames