This is kind of misguided since Apple isn't taking control of your devices -- you can use alternative HomeKit Home apps just fine without logging in.
(I run homebridge and hack my own HomeKit devices, FWIW)
What has happened is that iCloud is now required for syncing settings across devices _and_ being able to tunnel back to your Apple TV/HomePod (whatever is your home hub) and control things remotely - which is not quite how the article puts it.