I would say it’s a bit more nuanced than that. I have installed quite a few games on my Deck that have had serious issues that require their own unique fixes in order to work. I had a few games that had shader issues with flashing neon textures that required specific Proton versions to work, a few games that could never get past the main menu due to infinite loading that required reinstalls and using specific Proton versions, and one that required adding some additional commands on the startup in order to avoid crashes. I’ve also run into a few games where the Deck has quirks, such as one I played where the keyboard would cover the game’s text input and the keyboard would appear immediately after closing, which meant you could hardly read what you were entering text for. They do work eventually, so you are technically correct, but they require effort to fix that some people will not feel comfortable doing.
I’m not sure why these comments are so negative so far. If I’m understanding the article correctly, it is an optional setting to automatically open the app as soon as it is done installing. The Play Store isn’t just installing and opening apps on its own.