That is bollocks
That's bollocks and he knows it.
From Oracle there are Hyperion Planning/Essbase on-premise or Cloud (PBCS). You CAN use Excel as an interface (via the SmartView addin), but you can also operate perfectly well in the web interface (ADF-based).
I make no comment as to costs, but to say that enterprises plan on spreadsheets is just plain wrong. As background, I specialise in Hyperion Planning/Essbase/Financial Management implementations and have many FTSE100/250 companies amongst my clients in this regard.
The challenge is to get people to store data in the relevant tools, rather than creating islands of data stored in Excel, but that's true whatever the product is.