The post you’re responding to made it clear that the placement of the box on the map was arbitrary. There is absolutely ample space to orient the ride building to allow for a substantial miniland. Even as the poster positions it, all of AC - which we have considered a land or miniland for decades - could be converted to Monsters. Why, it even has a show space for the big Monsters show.
The idea that new lands need immense space is also deeply incorrect, a product of modern Disney’s incompetence. Compare the profound, sprawling failure of TSL to the tight brilliance of New Orleans Square (like Monsters, an urban setting) which features perhaps the two greatest rides in the Disney pantheon. Skilled designers can do a lot with relatively little space - in fact, such a layout would benefit an IP like Monsters.