Is data on when I turn the oven on, and how long I run it for, even worthwhile?

They wouldn’t be holding you hostage for it if it wasn’t.

I’ve honestly come to the conclusion that some companies have management that actually believes its worth while to collect the most meaningless telemetry data, even after the ridiculous cost of bandwidth, database storage, hosting, etc. which all become more bonkers the larger the dataset. I’ve seen the cloud bills for actual useful data, I don’t want think about how much they must be paying AWS/Azure/GCP to host such worthless data. There’s no way its at all profitable to do so

At the bare minimum, they’re going to use that data to figure out, on average, how much use it gets while under the warranty period. They’ll use that to further cut corners on the materials or other design considerations.