As in real life, everything is relative.
How well does the paint stick to the floor? If it is chalk, the question is quickly answered: Until the next rain. With paint, it depends on the quality and which binder is used. There are acrylic paints, emulsion paints, and own mixtures that are more environmentally friendly. The latter are also very limited in durability. A few rain showers go through, but long, heavy rain destroys a 3D picture painted with, for example, gouache-based paints.

The plastic colors are more robust and, depending on the surface, last for months to years. So the plastic issue is relative again in terms of sustainability.
Yes, it’s plastic, but it lasts much longer. Each painted house has more area. I am still looking for a suitable eco paint, but so far I am disappointed with the results. Maybe soon I will use only colored grains of sand or spices. i am thinking about it. Mandalas are made in the same way.