Title text:
It's important for devices to have internet connectivity so the manufacturer can patch remote exploits.
Transcript:
[A store salesman, Hairy, is showing Cueball a dehumidifier, with a "SALE" label on it. Several other unidentified devices, possibly other dehumidifier models, are shown in the store as well.]
Salesman: This dehumidifier model features built-in WiFi for remote updates.
Cueball: Great! That will be really useful if they discover a new kind of water.
Source: https://xkcd.com/3109/
Zigbee is local and if you really wanted to you can use Home Assistant 100% offline it will be just neutered and basic.
im not sure why all these people jumped from 'wifi' to 'internet' as if they were the same thing. no one should be exposing their automation devices directly to the interwebs
Sadly, many wifi-enabled devices only work with some proprietary cloud-service and even if not, they're only one configuration error (or intentional backdoor) away from talking to the outside. Better have something that isn't physically able to talk to the internet no matter how badly I fuck up its configuration and my firewall.
Clearly I just trust my abilities to disable a devices internet access in my router more than you. I also know that my risk factor is really low, because I'm not a journalist or a politician.
As well, I only buy smart devices that I can lock down, brands like LIFX & Shelly that have cloud services, but don't require you to connect to them for the device to function over LAN.
Honestly, having any of these vulnerable devices on your network is exposing your whole network, assuming the network is connected to the web.
Your best off using either a separate network for your smart devices with its own router, or setting up a vlan to keep your smart appliances and actual computers separate.
In this case the OP was explicitly about internet connectivity