Companies will lose deals unless they do what customers want. Eventually, that chunks up the software and makes it awful. That's just the nature of the beast, and it's no different than things were pre-computer.
I had a .gov customer that had a very specific ruleset about stapling paper forms a certain way, which impacted how certain processes worked after they were computerized. Nobody understood why, then we found out -- in a tragic accident, a key employee in one of the paper processes in the 70s lost an arm. They ended up stapling things a certain way to accomodate his constraint and optimize throughput. The practice spread to other areas. 30-40 years later, after the employee was long retired and dead, the process lived on.
In the case of something like Word, people who write need to do stuff. I probably use 30% of Word features, but in the 2 times in the last decade that I needed to create a document with a table of figures, it's there.