Folk songs aren’t historical sources, man. Every region has folk songs and stories about “refusing to convert,” “becoming a Turk,” “heroic resistance,” whatever. Greece has tons of them ... and most were later shown to be national‑romantic inventions created during the formation of the modern Greek state in the 19th century. They’re not archival evidence, they’re cultural storytelling. So I wouldn’t trust “folk songs” as proof of anything.
And again, prove me wrong. If Greeks were supposedly a major devşirme source, then show me one famous Greek Janissary. You can’t. Same with Armenians ... name me a single famous Armenian Janissary. You can’t. The reason is simple: in the early period, recruitment was more chaotic, but as the empire became politically structured, the sultans avoided pulling from groups that already had established roles or were politically sensitive. Greeks had their own administrative, clerical, and commercial functions within the empire. Armenians had their own merchant and artisan networks. These groups weren’t the target pool.