True, but that's tangential to the issue at hand.

To continue the physical home analogy, let's say you're a renter and your landlord has the ability and access to install something in your home at any time without you knowing. Maybe they include it as part of the terms for your upcoming lease renewal, maybe they don't.

Does that mean you should just accept it when they decide to install one of those devices in your home?

There is a giant difference,If you are a developer you might understand this better, it is much easier to have an application behavior setup from a config file or from a database then from code. So you have a config that looks like scan_everythin = false; and an update would flip this to true for everyone or for special users. Also with the hashes , the check is not done locally so the government will ask Apple "hey check those hashes you have stored against this secret database too and if you find even 1 match send it to us, here is a judge order so shut up and do it".

So after this the governments around the world job is easy, they throw hashes to Apple(and fortunately for Apple they can say they had no idea what original photos content was) where before the government would have needed to ask Apple to write new software and Apple could have said that it can't do it without starting a shit storem.