> Lotus Notes died because the web took over

Lotus Notes died because it was proprietary. Had it been open: an open server and open protocol, I believe every device would be using it today.

I had one good dose of that platform for four years. It was a biotech with ~100 people in five countries[1], and four states in the US. There were Notes servers all over the place, and it worked with skeletal admin resources on neglected, low cost Dell boxes. It worked for management, sales and the labs.

[1] US, Germany, France, Japan and Canada, in that order.

M365 is proprietary and it is widely used by companies