The market shifted toward more FPS games because of Doom, yes. But also, modern FPS games don't copy Doom slavishly.

Initially browsers were, in fact, copies of Mosaic, but over time they've branched out somewhat.

This seems note-for-note to be a copy of Notion, not just conceptually. It's a product designed so a sales team can tell customers: you can cancel your Notion contract and just add this low-cost option to your existing Office 365 subscription!

Sorry but I would replace Doom with Wolfenstein: Is every FPS a Wolfenstein clone?

This looks like a parity to Notion's feature set. Chrome wasn't a copy of Internet Explorer because it was a great leap forward in web browsers. Call of Duty isn't a doom clone because it has a storyline and semi-realistic weapons and graphics.