The mew measures are intended more for immigration purposes than terrorist security. They will screen out many many more ordinary criminals than terrorists, and provide the basis for tracking and controlling false uses of visas, overstays of visas, and many other immigration violations. The 27 'exempted' countries do not present an ecconomic immigration problem (which should have been a clue to anybody here what the main target is) and have a different (more high tech) immigration identification program comming into effect for them in some months. To maintain their visa free status, IIRC, they will have to implement some sort of an electronic ID system (thus the time delay vs the low tech measures for visa-ed visitors.).
Brazil, with no economic or illegal immigration problem, and not being targeted, to my knowledge, for terrorist attack has nothing to gain by such controls. They will gets all the costs of adding the security and irritating tourists and business travelers, and gain almost nothing in return, other than maybe catching a terrorist in transit through Brazil to the USA