because the issue isn't about access to your network, its the rampant abuses that could be done with it - a stalker/crazy ex could place a recording device that streams audio (only need 30kps) constantly or tracks someone with no repercussions or any of the security airtags has and without users knowledge. This is a classic "move technology forward with no regard to the consequences and who cares about privacy" move.
Developing such a thing, registering it with Amazon, Amazon approving it as a compatible product, setting up the integration with Amazon, ... sounds like something nobody would do when they could just use the mobile phone network instead.
i can not see amazon doing a good job vetting all the devices/not making it easy to setup a test/dev account and devices. and mobile phone network costs money for each device, sidewalk is free for all?