Well, 1.4x faster is a bit of an odd metric. I presume that means that connection set up times measured were on average
1/1.4 times as long for IPv6 as they were for IPv4, but there are other possible interpretations.

So really, that’s a convoluted way of saying it takes 29% less time to set up an IPv6 connection than an IPv4 connection on average.

I can believe that is likely in a scenario where one is dealing with IPv4 NAT overhead.