Actually, none of those games existed 20 years ago. That is assuming you do mean multiple decades. Quite a few did not exist a single decade ago.
The first MOBA was dota for Warcraft 3. WC3 was released in 2003.
The first Call of Duty was released in 2003.
The Grand Theft Auto FRANCHISE is more than 2 decades old. The question then is, what features attract people now to the game. Since you are posting a picture, we can say that was released in 2013 and is not even a decade old yet.
Minecraft came out in 2011.
Apex Legends, Valorant, and Fortnight are all released in the last few years.
Just chatting released in 2018.
WoW was released in 2004. Pretty much every game there is MUCH younger than it. I mean, DOTA 2 was released in 2013 so it is much younger.
WoW is getting old. It has changed a lot since it was first released.
Its initial audience has changed and the new ones coming in never played it, or its predecessors. Most people who first played it did not have a cellphone when growing up. What genres of games are popular changes over time as well. You do not see any real time simulations anymore. The people who enjoyed them have gotten older and do not have the time to play the long games they were when they first came out.
Young people have instant access to information and easy games on their phones. Phone games can be picked up and put down whenever they want. They can watch other people play games they do not have the time or interest in. It is like watching a sports match. They pickup their phone, turn on twitch, and watch the latest game.
We shall see where things go, but much like my beloved RTS genre, I do not expect to see any releases become major hits anymore.