Basically one spreads faster than the other so after a few iterations almost all of new cases are the new variant.
> How would Delta prevent A.30 from thriving?
Directly by driving up immunity, indirectly by coercing people to take steps to slow the spread of delta, which also slows the spread of a.30. Things like vaccination, social distancing, mask wearing etc...
> Why won't we become infected by Delta and A.30?
Because Delta probably give you significantly more immunity than a vaccine. Specifically infection gives both more robust and stronger immunity than the vaccines.
Basically one spreads faster than the other so after a few iterations almost all of new cases are the new variant.
> How would Delta prevent A.30 from thriving?
Directly by driving up immunity, indirectly by coercing people to take steps to slow the spread of delta, which also slows the spread of a.30. Things like vaccination, social distancing, mask wearing etc...
> Why won't we become infected by Delta and A.30?
Because Delta probably give you significantly more immunity than a vaccine. Specifically infection gives both more robust and stronger immunity than the vaccines.