After the final rift closed, the nature of the spark was different. Planeswalkers no longer existed as ageless beings able to rebuild their bodies almost at will. They remained exceptional mages, but their strength depended on skill, circumstance and the mana available to them. They could be wounded, exhausted and killed.
The rules of travel changed as well. Most portals and vessels that had once moved ordinary living beings between planes ceased to function. Crossing the Blind Eternities became the defining gift of a spark, while a planeswalker generally could not carry companions along. Venser, whose spark ignited during the crisis, stood at the threshold of this new age rather than the old one.
That reduction in power made the Multiverse larger in a narrative sense. A planeswalker could no longer solve every crisis by arriving as a distant god. They needed allies, learned the customs of the worlds they visited and suffered losses that could not be wished away. The Mending saved reality, but its deeper legacy was to make responsibility inseparable from planeswalking.