Are you implying that even very complicated software hasn't become easier to write over the past 15 years?

No, I think he is implying that major software is not a "mostly drag-and-drop" affair. In some ways, things have progressed and software is easier, but it's far from drag-and-drop for all but the most specialized problems.

Perhaps "democratized" would have been a better way to describe it - the point of that sentence was to convey that you don't always need a huge pile of cash or specialized equipment to make software these days. Major software absolutely requires incredible skill, cash, time and craftsmanship. But it is also doubtlessly cheaper and easier now than in years past. Though that's another post for another day.

Apart from Excel.

I'm implying that there's no large and widespread software ecosystem I know of that creates via drop-and-drag applications of any significant complexity. The closest to that that I know of is LabView.