Relativity does *not* compel the block universe. Motl said it very succinctly:
"What the possibility to cut the bread [block] in different directions means is that for a distant extraterrestrial cyclist, all spacelike-separated regions of spacetime are equally real from his perspective and they may include events on Earth which belong to our past, present, as well as future. But that doesn't mean that the reality of the past, present, and future on Earth has to enjoy the same "reality status" from our perspective."
--Lubos Motl on one of Brian Green's errors in "The Illusion of Time" from "The Fabric of the Cosmos" series.