alt Hacker NewsThere is an old post by Joel Spolsky that worked as PM in Excel a looong time ago, and he agree with you: "Why are the Microsoft Office file formats so complicated? (And some workarounds)" https://www.joelonsoftware.com/2008/02/19/why-are-the-micros... (HN discussions https://news.ycombinator.com/item?id=12471604 (393 points | Sept 2016 | 229 comments) and https://news.ycombinator.com/item?id=118909 (60 points | Feb 2008 | 20 comments))
One sentence that stood out to me from there was this:
> The bottom line is that there are thousands of developer years of work that went into the current versions of Word and Excel, and if you really want to clone those applications completely, you’re going to have to do thousands of years of work.
This is blatantly not true. Only a small portion of all those "thousands of developer-years" is going to be actively present in these products at whatever point in time, as a lot of those developer-years are spent on replacing the output of other developer-years.
It's the difference between 117 billion humans ever having lived, and 8 billion humans currently living (and just some number of millions at any point in time before the industrial revolution - we've been around for a while, supposedly).
And this is still ignoring that someone looking to reimplement Office would be racing towards something pre-existing, rather than trying to come up with it in the first place. A lot of those developer-hours were spent on design and research, rather than rote implementation.