At least in Calgary most of the infills were split into two lots, so you ended up with two home in what had been one.
My parents recently sold their back lot in Ottawa (they had bought the lot behind the house in the early 80’s when we moved there). Two infills went in behind them / which have no real lawn and to me are significantly ugly. But three homes now exist in where there was one.
Down here, when my wife and I build we specifically looked for an area that was zoned R2 meaning 1 house / 2 acre lot. So the minimum land around us is 2 acres — because I don’t like people