Of course, the biggest factor in this is the Christmas holiday and the ongoing quarantines due to the coronavirus.
In this time when everyone has to stay at home, the act of playing games can be perceived as a good therapy for players.
There is also the effect of the exciting Cyberpunk 2077. Because when the record was broken, more than 1 million players were playing the game. Likewise, CS: GO was another game played by over 1 million players during the record. The games that followed CS: GO and Cyberpunk 2077, respectively, were DOTA 2 and Pubg.
The games continue to come to our aid by not leaving us alone.