Re: Living in a bubble?
In Excel, tables is a big one for me. I'm not sure exactly when they were introduced. I don't think they were in 2003, and I skipped 2007.
More recently, =SWITCH() is pretty useful. You can do the same with nested =IF(), but switch makes it a lot cleaner. =SUMIFS() [like =SUMIF() but with multiple criteria] is useful, as is =COUNTIFS().
Spillable functions like =UNIQUE() are also pretty useful.