The above is only one side of it, and the people that think the contract is bad are usually commercial/pro photographers. Compared to any other buying arrangement a commercial photographer would enter into, it is very bad.

However, a lot of people do sign the contract and are happy with the trickle of money they receive. If you never intend to make any other commercial use of the images in question, are happy to trade value for getting any money at all and can provide all necessary model releases, then it may well make sense for you to give Getty access to some of your images. I would never hand over my whole stream or give them exclusive rights to represent me, but I could imagine letting them sell a handful of images for me, with the full understanding that I was being commercially exploited wrt those images.

It is, after all, basically zero-effort cash that you're otherwise maybe not getting. So don't let me talk you out of it, but really you do need to understand the contract fully, which will require reading up on a bunch of legal and commercial terms and finding other typical contracts to compare with.