.NET core was slower than mono which was slower than JVM for running real time multiplayer games (3d math, serialization, reading and writing from multiple stre

.NET core was slower than mono which was slower than JVM for running real time multiplayer games (3d math, serialization, reading and writing from multiple streams) as of a couple of years ago, did something big change With the runtimes very recently or is this just coding to benchmarks?