1) Home Assistant is not an officially sanctioned option by the devices and will run into technical issues regardless whether it's cloud hosted or not (as seen by the very post we're all commenting on).
2) Even if the above were not true, at that point you're back to an internet enabled smart home device system, and now we're simply picking which vendor to trust over the other. But in both cases, the option for the vendor to collect telemetry data about your usage of the products exists.
There is really no viable way for the typical consumer to be able to both have a good product experience for something like this, and to prevent a cloud vendor from having access to their data. Unless I'm missing something obvious.
2) Even if the above were not true, at that point you're back to an internet enabled smart home device system, and now we're simply picking which vendor to trust over the other. But in both cases, the option for the vendor to collect telemetry data about your usage of the products exists.
There is really no viable way for the typical consumer to be able to both have a good product experience for something like this, and to prevent a cloud vendor from having access to their data. Unless I'm missing something obvious.