When I rented an apartment in central part of large city for 2 years, I literally haven’t never seen people from 2 other apartments on same floor as me and maybe had one chat with last one. I rent house in suburbs, at nice cul de sac, I know names of neighbors in 2 houses and had chats with 2 more. So your mileage may vary A LOT. Although large city offers many more chances to randomly step up. Reaching literal center of city and it’s life in 30 minutes on subway is much different from reaching another burbs on car.

Yeah the point of apartments is not to socialize with the neighbors specifically, it's more that the increased density gets you walkability and density.

It's much more appealing to get to the street and walk when you have 4 cafes, a theater, two libraries and a gym in a 10 minute radius than when you just get to walk next to lawns for an hour.

And there's a point to be made for the added friction of a small home. The more self sufficient your house is the harder it is to convince yourself to get out.

Taking care of the lawn, etc, you will definitely meet your neighbors.