The fact of the matter is, yes, PopMart sold far better in Europe and South America than it did in North America. But, overall, the sales for this tour were disappointing and embarrassing. While we can sit here and carve up the globe and say 'Well, this was more about North America than it was the rest of the world' it is highly doubtful U2 see it that way. U2 up to this point, and really again after, had always OWNED America. It wast their home away from home, and the U.S. embraced U2 in a way it never embraced its own. Just four years after PopMart, what band was called upon to mourn 9/11 at the Super Bowl, the biggest single-day event in the U.S.? U2. There could have been no other choice.
So my point is, yes, they did in fact group too many shows together. There was no reason to try to play three shows in Florida, one in Tennessee, one in Georgia, one in North Carolina and one in South Carolina. And one in NOLA. That was too ambitious. However, you couldn't have combined the attendance in three of those shows and sold one out.
I am just saying that people need to keep these stats in mind when talking about U2 'ignoring' Pop. Whether a few very vocal fans love the album and tour or not, the rest of the world didn't, and it makes zero sense to ask U2 to revisit this period at the expense of the huge successes that went before and would come after.