Exactly the reason why Qatar World Cup happened in winter season because the humidity and temperature is not that much of a problem compared if they will commence the games in summer just like what we used to because the heat will become a major problem to the audience especially the players who are playing under the heat of the sun. But even if it's already winter season when the games happened in the recent World Cup, the stadiums still needed a lot of help to cool it down.
The schedule of FIFA World Cup in 2022 overlapped with some of the major European leagues and many of the clubs were even threatening that they will not release any of the players for the tournament. In the end however, FIFA was able to settle a deal between them and the clubs. However, for me this sends the wrong signal. World Cup is the most important tournament for the sport of football, and greedy clubs want it to be given a low priority. Going forward, I am sure that these sort of clashes will become more frequent.