I’ve got a similar setup (home assistant and smart plugs) and it’s been pretty trouble free for years and really useful.

I do agree though that smart home tends to be rather fragile if not actively managed towards simplicity and robustness

> They work a generous 90% of the time. The other 10% I use the physical wall switches to turn off

That sounds oddly low. Mine always work unless I broke something on the network in dramatic fashion