One thing I'd point out is that there are only so many ways to write a document or build a spreadsheet. There are a ton of business processes that are custom enough to that org that they have to decide to go custom, change their process, or deal with the inefficiency of not having a technical solution that accomplishes the goal easily.

Lotus Notes is an example of that custom software niche that took off and spawned a successful consulting ecosystem around it too.

> Lotus Notes is an example

TIL Notes is still a thing. I had thought it was dead and gone some time ago.