Thanks for the response! Refreshing to hear that it can actually work - I think the main difference between your setup and mine might be that I actually needed the mesh because I had bulbs in behind a couple of steel concrete walls. I installed always-on Zigbee outlets thinking that bulbs would route over those but never actually got around to debugging why they didn't.
Currently I'm also mostly on Tasmota-powered Athom bulbs. They work well, but after not powering them on for longer timeframes (presumably after their internal battery or whatever runs out) they forget my wifi and switch to setup.
After these experiences I'll probably go with dumb bulbs and smart switches/relays for our new apartment. Still keeping an eye on the market and open for recommendations though, mainly because I like being able to control light color through HA.
I think you've nailed the key difference for zigbee, indeed. And I'd love to share some first-hand insight about how Zigbee works with either intermediate repeaters or routers scattered around, but I just don't have any to share.
You did remind me of a thing, though: My Athom bulbs, with ESPHome, do have an annoying mode they drop into when their Home Assistant mothership is unavailable. They still work mostly like dumb light bulbs in this state, but they do a periodic blinky-thing (with a cadence in minutes, not seconds) that is annoying until the HA rig comes back.
But since they're running a copy of ESPHome that I compiled locally, that's almost certainly an ESPHome function that I can hack out/turn off/modify/whatever.
I don't have any direct experience with Tasmota. I remember looking into it with some giddiness several years ago (just because hacking on home electronics does that to me), but by the time it came to start actually buying hardware I decided to go in a different direction.
But I don't recall the Athom bulbs, with ESPHome, ever dropping out and not coming back. Even after the last move where some of them were in a box for weeks: If there was any difficulty, it wasn't something that took a lot of steps to resolve. I think I'd remember if it were challenging in some way.
So I'm lead to wonder what mechanism it is that makes your stuff go goofy with Tasmota.
Inside of these things is just a small power supply, an ESP, some MOSFETs and some LEDs. On-device configuration data is stored in flash right alongside the firmware itself. There's no battery, nor any no real-time clock (if the time is useful, it is set over the network).
Athom does publish steps for switching [some of] their hardware back and forth between Tasmota and ESPHome, if that's ever useful to you: https://github.com/athom-tech/athom-configs
---
More broadly, having smart switches and/or dimmers with dumb bulbs does sound appealing. I've got all of the lights in my garage on one smart switch, for instance, and it works well for that environment.
Smart switches would also Grandpa-proof the installation: If a dumb bulb goes out and Grandpa is watching the place, he can just swap it out and things would work fine. (Knowing my own old man, he'd probably use a dusty incandescent bulb that he's had in the glovebox of the car since he stopped to pick it up along the side of an unpaved road somewhere outside of Lincoln Nebraska in 1973...but it'll still work fine.)
But smart switches and relays alike want neutral wires. It's not always straight-forward to integrate them, as I've written extensively about elsewhere here.
And right now, I've got the usual lights in the common areas downstairs set (via the Adaptive Lighting integration) to smoothly adjust their color temperature based on the position of the sun. And I really like that function: I get intense 6000k light during the day that more-or-less emulates the ambient sunlight that comes in through the windows, and a much more serene 3000k light when it's ~dark outside. And nobody has to think about it at all on a day-to-day basis; it Just Works.
This is, quite frankly, pretty glorious to me in ways that I don't think I ever want to give up...so I'm stuck with smart bulbs in lots of places.
I actually didn't try ESPHome yet, thx for mentioning it. That will be my next experiment then. The adaptive lighting also sounds really cool, will try that as well.
Do you know if the Athom bulbs even have some kind of persistent memory that can survive longer timeframes without power?
There's only two kinds of memory in an Athom bulb: The RAM that is built into the ESP MCU (temporary, fast -- like RAM in a PC), and the flash ROM (permanent, much slower -- like an SSD in a PC).
Data in RAM doesn't survive for even a moment without power. Data in flash should be good for years and years with or without power.
Currently I'm also mostly on Tasmota-powered Athom bulbs. They work well, but after not powering them on for longer timeframes (presumably after their internal battery or whatever runs out) they forget my wifi and switch to setup.
After these experiences I'll probably go with dumb bulbs and smart switches/relays for our new apartment. Still keeping an eye on the market and open for recommendations though, mainly because I like being able to control light color through HA.