Many modern homes in Toronto are based on the open concept space. However, an open concept does not necessarily imply one large room with no separation. Dividers can stop echoes from forming due to unrestricted sound travel. They can also add some structure and privacy.
Building a wall may end up a messy business and produce very expensive mistakes. Portable or semi-portable dividers are cheaper and easier to install. They require no demolition to be removed should you like to get your open space back.