UK cellular tower and TV mast radio specialist Arqiva has been put up for sale with an optimistic price of between £5 billion and £6 billion, but its two core areas of business both have question marks hovering over them. Any mobile tower company taking a long hard look at 5G has to decide if it can get heavily into a new class of platform for small cells – notably cutting deals with smaller street furniture such as street lighting, rather than building brand new towers. It’s not so much that the existing macro cell towers are going away, just that will not grow. Arqiva, so much a dominant force in the UK, that it might be considered a monopoly,…