An absolute nightmare for security and privacy. Just say no.

As a hobby, yeah, go for it.

To save time and money, not so much. You will spend much more time in setup and debugging than you will ever recoup due to the automation. Same goes for the money.

I like mine. It has a lot of nice convenience features, and it feels good to have stuff happen automatically based on your presence. Scripting useful automations if a time-consuming hobby though, and if you're mostly just interested in doing voice control for lights it may not be worth it.

I'd recommend staying away from anything that connects directly to the wi-fi if possible. ZigBee lets you isolate the garbage hardware from the Internet so they can't be used as zombie devices in a botnet or worse, and have home assistant be the one point of contact.

I'm not a fan. Any exploitable issue with the software, and my house can be viewed by anyone from anywhere.

I've got zero smart devices at home, to the point of even using my TV as a simple screen only.

It's a great and rewarding hobby! But having cloud connected devices on the same network as your sensitive information is an issue.

Use a vLAN and IoT devices capable of local control. Use a self hosted hub like Home Assistant. Keep devices that collect sensitive information (like a camera) out of sensitive areas (like the bedroom). Then you should be reasonably secure.

I love the idea of having motorized blinds and windows that automatically open/close coordinated with thermometers to regulate house temperature.