Why then does vaccine inequity still exist

We know this is an aviation conversation but found it irresistible to share this well written APnews story on vaccine inequity with you. When we theorize on the factors responsible for the near collapse of aviation during the pandemic, we naturally select border closures and entry restrictions as the prime suspects. But are they really? Now more than 15 months on, surfing on gnarly 3rd and 4th waves, there are some countries unable to source and/or pay for vaccines. While others, we see, have 5, 8, 10-times the doses for their populations. If the mantra “we are not safe until we are all safe” is to be believed as the honest sentiment of many of our world leaders, why then does vaccine inequity still exist?