It is 100% going to be easy to get visa if you have a ticket.
You have no idea about the US visa system. A few years back, my B1 visa was put on hold for 6 months, just because of some administrative formalities. And many of my friends have faced difficulties with different types of visa. If you are a citizen of some of the developed nations, then it is relatively easy for you to get your hands on a US visa. But if you are from countries such as India and Pakistan, then it takes a lot of background checks and additional verifications to get a visa approved. In short, having a valid ticket doesn't guarantee you a US visa.
I have some information about the visa system in America and I visited this country once a few years ago back in 2017 when I had my job offer. Compared to many other countries and especially the other countries I visited in my life, America got harder rules for their visa system. But still, they hosted another world cup before and people had no problem with the visa system, that's why I think the government of America will not make hard rules for the visitors during the world cup.
Yes, I also understand that visa rules in America are very strict and if you cannot meet the requirements or rules that have been set, then no foreigner will ever be allowed to enter America.
But what you say is true that America will not tighten visa regulations at the upcoming World Cup.
Some of these regulations will be simplified and in this way many football fans will be able to easily come there to watch their proud National Team compete.
After all, FIFA must also have coordinated with the American government to provide a little convenience for foreign nationals who will come to watch the World Cup event.
It's already safe to assume that America will show some slack when it comes to their application to have a foreigner visit their country in aim to watch the upcoming World Cup but let's also expect that before someone can enter their soil, these people have been meticulously studied and searched thoroughly because safety is still a concern especially in an event like this where lots of America's enemy will disguise themselves as a tourist but they are not there to watch but to create problems that could include the tourists.