Talent or skills is essential but alone is not enough. while the size and quality of the talent pool helps it is not sufficient to explain the success rate, considering that there are similar or better quality talent pools which are larger in many countries around the world, but they don't have the success rates Israeli startups and 8200 ones specifically have compared to their home market and talent pool size.
It is not some conspiracy either, success as founder has strong network effects and positive feedback loops, right mentorship, access to talent pool, or access to funding and people who can open doors all becomes easier when your network already has some success. Similar reason second time founders have it easier they can tap into their personal version of a network.
It is not unusual to Israel/8200, the valley itself benefits from this effect heavily after all.