I used to manage a Domino/Notes environment back in my early days in IT.

Domino server was rock solid I never had to worry about it at all.

Notes client was clunky and not super intuitive (4.* through to version 6.01 I think) but was still quite a decent client. groundbreaking stuff for the time. I have mostly fond memories of it.

I was a developer at Iris Associates--I worked on versions 2 through 4. For version 3 I stuck in an easter egg in the About box. A certain combination of keys would produce a Monty-Python-like cut-out of Ray Ozzie's head and the names of the developers would fly out of his mouth. [This was when the software world was young and innocent and developers were trusted far beyond what they probably should have been.]

Lotus Notes was, I firmly believe, a glimpse of the future to come. In 1996, Lotus Notes had encrypted messaging, shared calendars, rich-text editing, and a sophisticated app development environment. I had my entire work environment (email, calendar, bugs database, etc.) fully replicated on my computer. I could do everything offline and later, replicate with the server.

And this was two years before the launch of Google and eight years before GMail!

In the article, the author speculates that the simplicity of the Lotus Notes model--everything is a note--caused it to become too complicated and too brittle. I don't think that's true.

Lotus Notes died because the web took over, and the web took over because it was even simpler. Lotus Notes was a thick client and a sophisticated server. The web is just a protocol. Even before AI, I could write a web server in a weekend. A browser is harder, but browsers are free and ubiquitous.

The web won because it could evolve faster than Lotus Notes could. And because it was free. The web won because it was open.