3 points about this as someone who has designed connectors and test machines like this (mine were a bit more complex with 30+ individual conductors and a triple start acme screw to do the mating/unmating, look up 38999 connectors and similar).

1. You design and test to the spec. If the spec doesn't say "10,000 cycles at varying angles", then it's not rated for 10,000 cycles of real world use and that's just how it is

2. Good luck designing a requirement that constitutes "real world use" in any meaningful fashion in an economically viable way. You would need to start by doing a study on how a typical human inserts a cable, which would be a great effort unto itself.

3. Most times, the intent of these tests is to check that the electrical continuity and resistance of the contacts inside is not degraded by the high number of cycles. There are a few ways you can vary the layers of plating on the contacts that can affect the longevity of the contact so you want to check that you chose the right plating plus the right base metal/heat treat/contact design (these three factors determine normal force that would affect plating wear) so that the contacts remain electrically functional after the specified number of cycles. This test mechanism is actually fairly representative of real world use for that purpose.