We just let the kiddies crack on and widdle in public but we are still here!
Every now and then you will note a comment here that looks a bit more ... insightful than the rest - it might be bollocks or not. Search the username etc. or follow the threads and someone will eventually note who made it.
You will find some remarkable people hereabouts. The rest is the usual noise of any other social.
Technical reason is they don't really want to do them and they are difficult to get right. Office365 does not run Exchange updates, so they don't get properly exercised. The only reason they haven't dropped support for in place updates is customer screaming but trust me, Exchange team would love to.
Proper Office365 way to update Exchange is build new machines, patch them fully, install new Exchange version and move all the mailboxes over.
On prem Exchange is being made as wanky as possible to run and has been for some years. Updates are excruciatingly painful and there is no technical reason I can fathom for that other than give them: "death by a thousand cuts".
We have an all in one Exchange box so no fancy stuff and it really is painful to watch updates and there is no technical need for it. Its not even a subtle nudge. I've had updates take multiple hours.
I'm old enough to remember when email (let alone the www) didn't exist. MS were eventually very clever in the '90s and noughties and have kept on top of things since. They don't have a total monopoly but quite a decent slice of the "market". The goal is silo off users in their cloud. On prem does not make them anything like enough cash.
They will lose a few customers to Linux and Apple but the full on subscriptions model will more than fix up the finances.