Almost anybody can use it, it is simple and reasonably intuitive - and most importantly - extremely flexible, so you can change your processes and workflows without much cost.
Then once processes are figured out and reach a more stable state, you can turn that Excel process into something more smooth, custom software or a more advanced tool. And you have a pretty good starting point for a spec for the software.
Easily? Yeah, right, after you pay \d{5,} dollars, after years of development, you get something that hopefully enables to run your business more effective.
Of course, we also try to get from Excel in business processes that require data consistency and automation and stuff, but first of all: Someone was able to write that excel and show us actually what kind of data/calculations is important to them.
I think excel is here to stay along with the email. Article reads like: "use this instead of email" (and buy from us). Everything has their place under the sun, but excel is as good as it is bad.
Leave out Excel just for finances and then we will talk.
