One of the bigger things I've ever built was a massive set of tooling based upon Excel + VBA + proprietary API. The old days ('00s). The best thing of developing in VBA was that the API was properly documented. Any function had documentation via VBA, plus via the primary tooling, plus via big old books. On top of that I had a premium support line to the developers of the API as I seemingly was one of the few worldwide actually using it. Heck, even a professor that showed up in the documentation was kind enough to help me for a bit. A shitty, but high-paid job for 10 FTE was reduced to a one-person show where the main job was adding intellect, not pay-for-clicks. Probably still is a one-person show. It's the one thing Python and R never achieved for me (note - I am lowly skiled at his): object oriented programming that helped, not hindered.