I'm not saying it can't be done, all I'm saying is it's usually harder to have a few really good cities when you also have loads of other less good cities to manage. At the most basic level, each settler you build is at the cost of another building that you could have built in your capital. For tall you only miss out on three buildings which is more than made up for from those extra cities. However, wide strategies lead you to delay 6-7 buildings in the capital straight off the bat, as well as the extra pop you miss out in the capital during those turns. On top of that are the science, culture and happiness penalties incurred. It will take some time before those extra cities start making more science/culture than what they cost but in that time you could be delaying techs/policies for a bit, which delays how fast your capital grows. In addition, if you fall into unhappiness for a bit while settling all those cities, that will slow down pop growth. You're going to need more workers, so either you spend time building more or you ration them between cities, which again leads to less of a powerhouse capital. More cities also means National Wonders come later/take longer to build, also slowing down your cap. And finally, generally Tall tends to mean Tradition and Wide tends to mean Liberty (of course, not always the case, playing a wide tradition game as Spain right now), and Tradition as we all know is OP for all them food bonuses, helping you get a crazy good cap.

On the whole, while you should definitely have a very good cap even when playing wide, when playing tall you can often have ridiculously amazing capitals which are just harder to achieve on wide. Other than ICS Sacred Sites rush (which probably isn't the strategy you're going for as Brazil), going wide doesn't give that many bonuses to culture victory and tall is probably just way easier/more helpful. I'm not saying wide can't be done, I'm just saying tall is the more efficient way to go about it with that civ and victory type.