Because the average computer or smartphone only has one 802.11 wifi adapter.
Therefore, it must cycle between hotspot and client mode on some regular
interval to ensure that all nodes it comes into contact with can be serviced.

Do not forget - the 802.11 wifi adapter switches between hotspot and client
mode to enable connections, and then the Node software runs both a server
socket and client socket at the same time.  This is regardless of what mode
the wireless adapter is in.

Also do not forget that this protocol can run on any type of networking
connection.