Notes was in many ways much better than Outlook. It's a shame it got sold off to the crapheap and abandoned.

It was a great technical idea (email as a replicating distributed database), but I heard the user experience was not great.

Friction kills both mechanical devices and software products. Work on removing friction if you want your gearbox, or your software, to last.

"email as a replicating distributed database" sounds a lot like something that could now be approached with new blockchain technology.

Why, yes. Blockchains don't necessarily require a proof of work; git is essentially a blockchain.

I think I'm one of the few people who actually developed a Lotus Notes application. It was well received at the time doing standard (template) letters!