I kickstarted Dead Matter back in 2019 and in 2021 it finally entered Alpha. They never ordered steam keys and 20,000 people had to wait a month so they could grab steam keys 100 at a time per day. Steam is not an easy thing to get keys from and setting up the automation process is daunting for a single person, especially when it is your first time doing so. Steams own guide shows:
Q: How many Steam Keys can I get for my game?
A:Games and applications launching on Steam may receive up to 5,000 Default Release Steam Keys to support retail activities and distribution on other stores. After that, all Steam Key requests are reviewed on a case-by-case basis.
And getting those bulk keys lined up and available for every itch.io purchase is a pain in the rump. There is a lot more that goes into this issue than just updating a check box. You have 2 third party companies that are agreeing to share access. Do you really think Steam would just hand out keys for something you would normally pay for without verifying? You will get your key in time, in the mean time you can still download the game here and add it to your steam library as an external game. This honestly isn't a hill to die on as a consumer, and honestly isn't a very fair criticism of a game developer. I make text based games that are 1000000X lamer than this and it takes me 400+ hours to get 1 game out. This had to of taken months to build and they were still gracious enough to give it to you for $1. and some pocket change. No one owes you there labor, its hard work doing this and in the Indie Game sphere these technical issues happen all the time. We don't have a direct phone line to Steam like AAA studios do. We have to wait on hold like everyone else. My suggestion is go to any game engine and spend 10 hours building anything at all. Most likely all you will have is a single untextured moving object and a premade asset with mood lighting. I am honestly just astonished at the outrage that is happening. Shame, shame.