This worries me not because of any open computing concerns, but because of how FUNDAMENTAL general purpose computers are to nearly every decent paying professional job out there. All of them. No one daily drives Excel or Salesforce One or edits video or codes websites or balances accounts in Quickbooks on an iPad. Literally no one; we're decades away from that being mainstream, if it ever happens.
Everyone needs to be computer literate. Being a wiz on your iPhone or iPad does not, in any sense of the word, make you computer literate. Kids growing up with these closed-off devices quite literally destroys the fire of desire for learning how computers work, or even accidentally gaining a glancing knowledge with them enough to hold a good office office job.
Companies like Apple endlessly mouth their desire to get more kids to code, then their arms release devices so closed off that even trying to take a quick peek at how they work triggers eighteen system integrity protection alarms. You can't have it both ways, Apple.
Well, whatever. I don't really care. It just means more ultra high paying jobs for me. Apple (and Google, and to a lesser degree Microsoft) are literally actively sabotaging their own talent pool, guaranteeing that they'll never be able to hire enough people while paying the ones they do hire a ton of money.