The conspiracy theory is that FIFA pushed for the games in 2030 so can have the US host the games again in 2038 due to the rotational rules.
Ineligible regions: FIFA rules block continents that hosted the prior two tournaments from bidding.
Open eligibility: Because 2030 spans Europe, Africa, and South America, and 2034 goes to Asia, those four confederations are ruled out for 2038.
Limited competition: Only North America (CONCACAF) and Oceania remain eligible, but Oceania lacks the required stadium infrastructure, leaving the U.S. virtually unopposed. FIFA also has the same issue as the Olympics in finding locations that want to host but won't leave a stain on the organization when the white elephants show up afterwards. There is only a single 40,000+ stadium in all of Oceania while the US has over 150. (Note: Australia is consider part of Asia for FIFA since the Australians wanted to play a harder schedule then Oceania can provide).
The reality is for the rest of the world, hosting a World Cup is normally an economic loser, but for the US it requires almost no effort as they have the stadium capacity could host the World Cup ten straight times and not play in the same stadium twice. They just need to switch to sign on the stadium to the closest city, bring in real grass (which American football players are beyond pissed that the owners then removed it) and they are ready to host.
FIFA may be corrupt (I can probably remove the words "may be") but they understand that World Cups making money is what keeps the best players coming back and owners allowing the players to come back.