The kabbalistic thought of the Arizal did not necessarily negate the works of previous scholars.
The philosophical perspective of the Rambam and the kabbalistic approach of Rabbi Kordovero are not now viewed as mistaken and wrong, nor as deviant.
The idea here is that all these approaches are considered to be true, but they serve as partial perspectives within the all-inclusive framework of the Kabbala of the Arizal.
The previous perspective was not wrong, but rather an isolated occurrence, correct within a particular framework, within particular coordinates and limited parameters.
It is correct as an individual occurrence and within one world, within a massive, infinite framework of possible worlds.
Accordingly, the perspective of the Rambam is still established and firm, even though it describes only one piece of the picture.
The way the Rambam, and somewhat similarly, the author of the Tanya, describe the concept of reward is dependent upon a particular approach, and even, to a certain degree, upon a certain personality’s intellectual understanding.
However, it is understood that other conceptualizations and other perspectives are not to be rejected, but are, in fact, correct in individual occurrences, and they appear when appropriate.
Rabbi Adin Steinsaltz