I think that's generally true though playing music is a little more freeform. (And, guess what? Voice assistants tend to be worse at that.)
The problem is that you have many many billions of dollars have been sunk into making these devices about more than setting alarms and timers. There's actually been a lot of pretty amazing progress. But it's yet another one of those things that getting to 90% to anyone but techies who want to fiddle with their smarthome stuff or otherwise play with the technology.
They might have a sudden increase in usefulness when smarthome stuff is more common, although smart bulbs are a bit of a hassle in most switched outlets, because the switch is usually more convenient.
Maybe they'll add an app that lets you browse possible commands so it's more discoverable.
It's probably true that a well-integrated smarthome would benefit from voice control.
But I'd observe that I'm going up to my brother's tomorrow and he has all manner of timers and other WiFi-connected stuff and none of it has any sort of centralized control and that's pretty normal even for people who have a lot of that sort of thing.
And, yeah, the only smart light thing I have at home is one thing that doesn't have a controlling light switch and I used X10 for it for years before I got an Alexa.
The problem is that you have many many billions of dollars have been sunk into making these devices about more than setting alarms and timers. There's actually been a lot of pretty amazing progress. But it's yet another one of those things that getting to 90% to anyone but techies who want to fiddle with their smarthome stuff or otherwise play with the technology.