I think there is some 'sensational' headlining there. From the story
Currently, citizens from Commonwealth countries can only join if they have lived in the UK for five years.
But in a bid to recruit more servicemen and women to the Army, Navy and Air Force, the Ministry of Defence is lifting this rule.
...snip...
It means people from Commonwealth countries - including India, Australia, Kenya, Fiji and Sri Lanka - will be considered for roles, even if they have never lived in Britain.
The government already allows 200 Commonwealth citizens who have not met the requirement of living in the UK for five years to apply for a limited number of jobs every year. They
introduced the rule in 2016.
Now, that cap of 200 will be lifted.
...snip...
Applications from citizens of countries outside the Commonwealth will not be accepted, the paper adds. Citizens of Ireland and also Gurkhas from Nepal can already join because of special rules.
So it is not "anyone". It is still "commonwealth", they've just relaxed the residency requirement.
So, my understanding is that nationals from China, America, Iraq etc. etc. still cannot join. But why let the truth get in the way of a BBC attention grabbing headline!