Maybe our company is an odd one out but I'm pretty sure that number is more like 20-30%....
Out of a team of 10, 2 of us do about 50% of the work. 3 do about 30%, and the remaining five do about 20%... With probably two to three of them doing effectively nothing most of the time.
In our team isn't abnormal.
IMHO this is just hopium.
There's no indication that they will not work together since they need each other for their own separate selfish reasons.
They will use each other as long as goals have not been met.
When those goals are met then they will have a falling out. And at that point it's too late for the rest of us.