I had banner crops from my three apple trees last year to the point I had to prune out many small apples so branches could support the weight. That usually means a down year after and sure enough my flower production so far is pitiful, even on the Dolgo crab. Golden Delicious hasn't started yet but should be soon as I picked flowering seasons to overlap.
I live in the country and I'm seeing lots of blossoms driving the roads this year but not so much the 'wild" apple trees I've driven past for decades. Flowering crabs in town are looking real good. I know of a large mature Dolgo on a main street in a local town that I've picked before to make jelly and when I was in town the other day I made a point to give it a good look as I drove by and it was real light on flowers too. I know of another large one in another close town that I'll check next time I'm there, if it's the same then that confirms to me it's species specific, around here anyway.