Chrome and Firefox are as secure as Safari, if not more, banning them is a commercial choice not a technical one.
iOS exploits still exist, there's no real advantage in Apple sandboxing apps, they are routinely leaking users data and being exploited as well.
OTOH Apple refusing to implement certain web standards is proof that they cannot guarantee a safe implementation, which is a reason more to allow better browsers on their platform.
Chrome and Firefox are as secure as Safari, if not more, banning them is a commercial choice not a technical one.
iOS exploits still exist, there's no real advantage in Apple sandboxing apps, they are routinely leaking users data and being exploited as well.
OTOH Apple refusing to implement certain web standards is proof that they cannot guarantee a safe implementation, which is a reason more to allow better browsers on their platform.