This is the second article blithely praising cd key's I've seen on windowscentral. A comparatively technically grey market keyseller( vs 3rd part platforms like g2a). There are plenty of verified key resellers that you can see on isthereanydeal.
You don't want any unnecessary layers between you and your games library in the cloud. If steam removes your game for any reason you can simply send Steam Support a screenshot of a receipt from a verified reseller/or page on their site with the key shown and they'll reinstate your game. Cdkeys your SOL.( Well technically. I've seen g2a mitigate key banwave waves that come across there attention. And correspond with the developers.)
My games library is all I have going in my life so even if it's one in ten thousand. I want to know it will always be there.
Obviously this is more relevant to g2a and the like, which almost nobody reports issues with if you buy keys with a 99% rating. But according to my research from comments. Credit card charge charge backs happen up to three year's. So games can still be removed after you've had them in your library for a while.
That said it's clear from my post that buying from these places is far from foolish. And I'm glad that a reputable tech news site lends credence to Cdkeys to assuage customers nerves. When I got the digital only Series S I couldn't buy dirt cheap used games. And they filled in the gap. I now have a Steamdeck. Steam Sales and PC only verified resellers I'm glad to have a library of games I know will always be there