A plant’s needs dictates whether it is suitable to be kept indoors. An indoor Bonsai means that it is in a location that is not its normal growing habitat and would not do well outdoors.
Tropical or sub-tropical species would be known as indoor when growing in a temperate climate area. A deciduous tree would be known as “indoor” in a tropical environment. They would each reqiure artificial conditions to maintain good health. Some trees grow better than others in artificial environments but they all have specific needs.
A bonsai plant can make a good Christmas gift in almost any location in the country as long as you take into consideration your specific climate conditions.