What else did you think anyone meant by NIMBY?
Usually it seems that people who are moderately opposed to two houses on a lot would be rioting in the streets over a 150-unit building. But I agree, it's a better way to achieve the same outcome.
The term originated to describe opposition to the placement of unpleasant developments that wouldn't be objected to if placed elsewhere (think landfill or meat-packing plant).
It now roughly refers to anyone opposing greater density in urban environments. (This is different enough, already, that we should probably coin a new word for it.)
You're using it to mean -- what? -- opposition to any development on aesthetic grounds?
We're pretty far afield, now.
I'd also (tacitly) oppose large single family homes replacing small single family homes, but that's because I'd prefer to see even larger apartment/condo buildings. When each project is so politically expensive, it's important to get as many new units as possible out of each one. (Looks like defen is on board with this idea).
When two single family homes on a lot is encroaching on a community's threshold for permissible scale, usually a large apartment building would be out of the question. So I'll take what I can get.
At a 2:1 or better multiple (new units : demolished units), these conversions might be decent. You could increase a city's housing stock 2x that way, and it'd be a less drastic change than dozens-hundreds of skyscrapers needed for the same effect.
Is this not the textbook definition of NIMBYism?
Example happening in my town: builder buys a normal-sized house on a large lot for $800K. Knocks the house down, subdivides the lot, and builds two bigger houses on each lot, and sells each for $950K. If anyone complains, they get written off as a NIMBY who is opposed to density.
Due to local regulations, you need more driveway curb cuts, so the tree-lined street starts to become less tree-lined. You now have two 3-story townhouse style homes right up next to mid-century ranches or bungalows or Cape Cods and it looks garish.