Open and hackable products have a niche user base, so these users get a niche set of options. The only way to get mainstream products to play to this tiny user base is to demand that all products be open and hackable by fiat. Otherwise, there’s no incentive from anybody involved (manufacturers, app developers, etc.) to give them something that can run both their banking app and some open source app they compiled themselves. There’s a lot of dancing around the security effects this will have on “normies”, and although there are plenty of armchair proposals I haven’t heard one that doesn’t obviously degrade into some sort of alarm fatigue as both legitimate apps and malware tell you to click though a dialog or flip a setting.