It's actually one way this story about the apocalypse is more hopeful than the present day. We don't need the internet to make most of the things in that story work, but in our timeline we'd add it anyway to get and sell those good analytics.
And no one has really come up with an alternative: home assistant is good, but it's not for the non-techy.
I will squarely blame IPv4 for some of this: NAT has meant that the key application people might want to use is broken by default (remote device access) without mediation servers.
No, practicality is not the main reason these unnecessary connections are added. The main reasons are 1. to sell and enforce subscriptions and 2. to collect and sell data.
Is it just easier to get your car seat warmers to work when they can connect to the internet and make sure you're paid up?
Not a luddite but, aside from a couple of Alexas, just no need for any IoT.