Nowdays everything has internet access. And especially IOT-Devices are a good target for hackers.
Why? Because nobody cares about them after setting them up. And even if security holes are found, most vendors do not care about it and patch those. And even if there are patches available most users do not care about installing patches on their IOT-Shit-Devices.
Usually hackers install a bot on your IOT-Device. There is on on it, trust me. Sooner or later every IOT-Devices become a bot. And such bots are later used to DDoS other services or mine monero or whatever.
So you definitely want to put all your IOT-Device into your DMZ.
A DMZ can be configured on your Router. It is a special place for all your insecure devices that need to be connected to the internet.
The DMZ does not make your devices secure, they still get hacked, but at least they cant infect your local area network devices as well. So at least your computer stays safe.
Every modern router nowdays has an option to assign certain devices to a DMZ, make use of it.
Or even better throw your IOT-Device out of your window :P
Help to make the internet a little safer ;)