Check out the concept of 'enterprise spreadsheet management' as a different way of thinking about the issue of Excel in critical business environments.
This perspective recognises that nothing beats Excel as a source of financial innovation and 'can-do'. The problem is that few want to recognize this essential role. The large software vendors need to demonize the issue to sell licences to their replacement solutions. The result is denial at every level.
Much better to appreciate the core strategic value that Excel offers and not confuse it with the essentially tactical value that an individual spreadsheet offers. (Though a tactical spreadsheet can be valuably tactical for 10 years).
The answer is transparency. Once one buys in to wanting to know what is going on then enterprise spreadsheet management can really help.