The U.S. visa is one of the most difficult. Only visas from England and Australia are more complicated, at least for Russia. Canada was easier in this way, you could get a work visa and many engineers went to work in Canada because the visa there is easier and the social guarantees are better.
I believe that during the championship the USA can simplify entry and exit for fans, as it was done for the World Championships in Qatar and Russia. In addition, all of Europe can travel to North America without visas, so I think that a lot of people will come. Air transportation between Canada and the US is excellent, so traveling between the cities will not be a problem. I think the biggest problem may be crime, especially in Mexico, but I think the fans will be guarded heavily.
I think that for fans the matches in Canada will be easy to attend.
It is true that you agree with what you said that the process of watching the World Cup live will get various conveniences and simplifications. For now the process of obtaining a visa is very complicated, but I think this will be different during the World Cup.
The United States will be the venue for the most matches on a basis of 11 cities, followed by Mexico with 3 cities and finally Canada with 2 cities. With the addition of teams to 48 countries, the number will automatically be 104 which are divided into 12 groups.
It is logical that FIFA's main bet is on the USA as the richest country in the region and in the world. I think there will be no problems with the broadcast from the USA and with the movement of fans between cities cause in the US most developed air service in the world, after europe I guess.
Messi apparently moved to Miami cause he probably wants to participate in the World Cup once again in 2026.
Mexico is here with the Canada and the U.S for fans from South America and the Caribbean could attend matches of their teams without visas and have no problems with communication, because most of them also speak Spanish.
What was surprising that only 2 cities in Canada that were involved. It is strange that Canada was not given at least 3-4 cities to host, because Montreal, Ottawa and Vancouver are big enough cities with good air connections.