What's worse than that you can't turn the switch off from a controller is that you can't turn it ON from a controller either. You can only wake it up from sleep, but not turn it on if it is off. It's such an awful, electricity-wasting design... I leave it in suspend most of the time anyway, but I really wish I could easily turn it off more easily. You should have the option for either one available! And the controller should, of course, be able to turn the system on.
On that note, the way that Home button works is pretty bad too, I have had more than a few times where I hold the button down... only for it to not wake up the Switch, it failed to register. The light moves back and forth for a few seconds but nothing happens. So I need to try again, and eventually it wakes the thing up. I don't think I have any other modern consoles which can't even wake up reliably... the Wii and Wii U certainly have no such issues, and they also can actually be turned on and off from their controllers. But there are of course a whole lot of things about the Switch OS that are horribly bad and backwards compared to the consoles that precede it, the 3DS and Wii U particularly, so that should be no surprise.