Is excessive nocturnal emission a compensation from Allah the Almighty for abandoning masturbation, based on the noble Hadith: "Whoever abandons something for the sake of Allah, Allah will compensate him with something better"?

Congratulations on repenting from masturbation. You must also repent from watching forbidden images, as nocturnal emission (wet dream) is from the play of Satan and there is no sin in it. Its frequency, however, might be due to watching those images.