I agree, those spots are not a concern. Perfectly normal in Miltonias (and Oncidiums in general).

Tiny black spots are the result of damage from any one of many causes. The commonest cause is probably bumping the leaf or brushing it against something else. It often happens on the ride home, or when carrying plants to the sink to water.

Insect, fungus or bacterial damage usually causes larger spots.

Helpful info. Thanks.