Yes it is in demand! From the 55+ market to young families, more and more people are looking to one level living for ease.
It's not for everyone. In our area many of the one level living homes have one bedroom on the main level plus will have a full lower level with one to three bedrooms. This may not work for a family with infants or young children as parents will want the kiddo's bedrooms on the same floor theirs.
Many one level living homes however have at least two bedrooms on the main level if not three.
I recently staged a model home that is one level living with one common wall. A townhome so to speak. These are higher end and due to the townhome setting are more likely to appeal to the 55+ who wants the one level living but not give up the space or luxury. These would also appeal to young professionals who want the luxury but not the hassle of maintaining a yard.
Most of the 55+ townhomes will have a wonderful open concept that is great for just you or for gatherings of friends.
The entrance to the Master will be convenient off the main living area.
You will many times find a second bedroom on that main living level that is wonderful to use as an office if that fits your lifestyle better.
If you are lucky it may even have a wonderful sun porch!
Although two story homes are still being built everywhere, more and more you are seeing one level living Townhomes and Ramblers being built and in demand. If that is the lifestyle that appeals to you, take the time to see what is available.