Can it fit higher currents than nominal? Is it safe?
This is a difference in peak current and continuious current.
A random XT60 supplier from a web search quotes:
Max Continuous Current: 60A
Max Peak Current: 180A
(This supplier/manufacturer doesn't specify how long you can pull over 60A before it fails; this is likely a question of heat dissapation, which will vary slightly in each design and probably between XT60 manufacturers. But there are also usually limits on how long you can run a 70C battery at 70C discharge rate for similar reasons, so you will want to compare datasheets and pick complimentary parts.)