Users attempting to sideload an app would obviously be warned, not to mention various other methods of malware scanning / sandboxing which can alleviate that non-existant issue.

Hope the sandboxing is really strong.

Vulnerable people can be walked through malware installations over the phone, or via guided workflow.

Also, naughty nations/employers can pre-load spyware onto devices they require people to use.

Definitely excited to see what the best use cases are but will await headlines this year about misuse.