Gojo didn't lose in Jiu-Jitsu Kaizen because in the sequel we find out he actually won. Gojo grew up lonely, suffocated by his clan, raised like a weapon by a crop system. But his dream was simple for Yuji and the others to live long happy lives.
So at the end of JJK, he killed the crop higherups and left trusted allies to carry the torch. Even Gaku Ganji changed, telling the next generation to live without fear of dying young. And 68 years later in the sequel, we see a different world.
Sorcery isn't stealing childhoods anymore. Every mission is done as a team with full support from the higherups.