Different kind of applications. GaN has no reverse recovery at all and a way smaller gate source capacity and threshold voltage so you can crank up the frequency higher.

But GaN conducts heat worse and also anything that can withstand more than 650V becomes a huge die due to no vertical mosfet tech in GaN yet.

SiC is more or less like super Silicon, almost negligible reverse recovery, very fast switching, way smaller gate charge and a 1200V 1700V is economical and very performant.

For high power like 10s-100s of kW SiC is the best. Higher than that passive components become so big you don't need as high a frequency so you would go with Si IGBTs, lower than that GaN allows you to increase frequency by a lot and reduce passive components size AND in a lot of cases total losses.

So yeah, don't expect to see GaN in a car power train and SiC in a server power supply.