Matisse didn't get the perspective "wrong", he painted it the way he wanted it. He flattened the perspective in the room, and altered it from how we perceive perspective with our eyes.
The question of getting perspective "right" applies only if you're trying to paint in a realist style, that is to create an illusion of reality and depth in a painting. If that's not your aim, then you can't get the perspective "wrong". And it's not that Matisse didn't know how to get it "right" neither; he just chose not to do it that way.
A painting is a ultimately a representation or expression of something recreated in two dimensions, it doesn’t have to do it as an illusion of three dimensions. Western painting styles before the Renaissance didn’t use what we now think of as traditional perspective (e.g. Gothic). Chinese and Japanese art forms never have. Cubism deliberately breaks up perspective, representing a single object from several viewpoints.
Don’t be deceived into thinking Red Studio is a totally flat painting or style. There's still a sense of depth to the room, created by the arrangement of the elements. For instance, there’s a line on the left where the floor and wall meet (1). The furniture may be reduced to outlines, but the table edges still angle in as they get further away (2), as does the chair (3). The paintings at the back are clearly propped against a wall (4), even though there’s no separation of the side/back walls (5) in the way there is between the floor and side wall. But we read the edge of the large painting as being in the corner anyway.
It could even be said each element of the painting does experience perspective, but is presented as if the artist were seeing only it. The chair is in two-point perspective, the table in one, the window also recesses to a vanishing point. They are juxtaposed, almost a collage of different views.
