I suspect everyone has a different answer to the question of poetry and each answer would be valid. Resonance has no monopoly. I like the description given by Dylan Thomas. There are several versions of its origin online.  I don’t know which one is true so am breaking academic law and quoting without reference. It feels strange to do so!

‘You can tear a poem apart to see what makes it technically tick, and say to yourself, when the works are laid out before you, the vowels, the consonants, the rhymes or rhythms, ‘Yes, this is it. This is why the poem moves me so. It is because of the craftsmanship.’ But you’re back again where you began.

You’re back with the mystery of having been moved by words. The best craftsmanship always leaves holes and gaps in the works of the poem so that something that is not in the poem can creep, crawl, flash or thunder in.’

The sense of a poem tapping into a universal truth like an archetype or some other manifestation of the collective unconscious is often referred to. Poems need spaces which can bring different meanings to different people. Back where this began; poetry is individual and part of the success of a poem might be measured by the number the people it resonates with.