This problem isn't that hard, screen readers had to handle this exact issues for years. Inaccessible websites where the labels aren't properly associated with their respective form fields do exist, but aren't that common.
Everything shown to me so far has been a solvable problem by scripts/xpath template/creation logic. I've handled all of this for over 10 years with one script. When I see it finding everything and associating them with correct external labels, then they have something. Otherwise I am concluding it non-functional and a long since solved problem where ML is over-engineering.