It was an era when Windows had near total Desktop market share in businesses - and Notes violated all Windows UI conventions. Enter MS Office (pre-ribbon) and LN was toast.

MSFT was so dominant back then that Gates had to rescue Apple to keep up the appearance of a fair market!

Lotus 1-2-3, et al, were killed by MS Office. But Lotus Notes was still selling 20+ million seats a year in 2000.

The web killed Notes, not Microsoft.