Sure looks like a crabapple to me. Most Prunus species (crabs are Malus but in the same Rosaceae family) will not hold their fruit this late in the season - crabs will. And fruit size is all over the book depending on cultivar - from as small as 1/2" to big 2" plum sized apples. To confirm, cut a fruit in half across its circumference. It should look just like a mini apple inside. A prunus will have a single pit.

Yes, esh_ga, I'm in the Netherlands, in a relatively cold inland area. It's a zone 6 on the map, but I think it's more 5-ish. Yes, I was concerned that the laurel hedge was allelopathic; I'd read conflicting reports on this. But certainly, I do see a lot of healthy trees growing next to laurel hedges, so perhaps I don't need to worry. Whatever I plant, it's going to look pretty puny for a few years next to that monster hedge. (Which I wouldn't get rid of for the world, what with the barn and all.)

I probably have about a dozen Prunus serotina in the yard, ranging from young trees to the largest which is about 50 years old. These are rangey trees with craggy bark in maturity. Flowers are nice but not super showy. IIRC fall color is yellowish and they tend to lose some leaves early, perhaps due to leaf diseases? It is Prunus afterall. It's a weedy tree and seeds prolifically - I am always weeding out seedlings. Personally I would grow this tree in more of a naturalized setting, not a formal one or as a lawn specimen. Mine are all in the back yard. On the plus side, this is a fantastic wildlife tree. Pollinators love the flowers, birds love the fruits, and it hosts many butterflies and moths. I have observed on more than one occasion a female Eastern Tiger Swallowtail butterfly laying eggs on the big Cherries, unfortuntely much too high in the canopy for me to collect the eggs! Birds love to hop around the trees looking for insects, and there's a squirrel nest in my biggest tree. Also the leaves are small, and don't need much raking.

TY! That's possible. I don't recall seeing any fruit on the trees in the back at all, but can't admit to paying much attention to them. I checked to see if this Prunus is dioecious, but several sources agreed on monoecious. The 2 in my front, and 3 in front across the street are heavily covered with fruit like this. The ones in the back are flowering heavily, and look identical to my amateur eye, but no fruit. There's a lot of it back there, along the tree line between properties. IDK how many individuals, at least 6. I can't tell which, if any, of the entities along this property line were deliberately planted at some point in the past. House builit in 1901, so there's been plenty of time for volunteers to exploit what looks like it's always been an un-mowed tree line. And no idea how to estimate the age of a Prunus. The two out front seem to be deliberately installed, exactly symmetrically placed at each corner of the house. It's a quiet street, leading only to other houses, with very little traffic most of the day to disturb birds, AFAIK. IDK what additional close-up pics might be helpful, but glad to add them if told what to capture.