And almost all of those, except maybe the router and phones if the users are technically sophisticated enough, will be locked down and refuse to obey the user. When Linux gets Tivoized, well-meaning devs have helped corporations abuse their users and customers.

Yes, of course, but as an 'Application Platform' Linux obviously not ubiquitous.

There are a number of free and commercial substitutes for Linux that could be used at that embedded level and of course, they are perfectly encapsulated and monolithic: your 'fridge' is not a platform wherein there needs to be some degree of OS-level integration with other bits of software. From a systems perspective 'it doesn't matter' what OS is running on your refrigerator.

But it's moot: there is no inherent morality in 'free software'. Software is just another good, with different means to distribute, one of which is FOSS, which is really great, but it's only one piece of the puzzle.

Yes, but the fact that those run Linux as against anything else is providing extremely tiny amounts of value.