In case of modern appliances, you are not the only customer/user of the product. Other customers are various advertisers that are interested in data about you. The updates provide enhancements for these other customers.
IMHO, IoT is a clusterfuck because it's preying on users' past goodwill towards computing. Historically, computers have worked "pretty well" (especially in the last couple decades).
So users, when looking at a network-enabled fridge, toaster, etc. logically assume "Oh, this will be like my laptop."
What's not apparent to them is how good modern computing has gotten (unless they remember the 90s), or that the companies making IoT stuff have no prior experience in software, or that there are effectively no certifications, standards, or laws around IoT quality.
Tracking is not even the most harmful aspect.
Tracking is a requirement for targeted psychological manipulation (AKA advertisement) including voter manipulation like Cambridge Analytica did.