The Cave 1 manuscript is the fullest, eleven columns, copied around the first quarter of the first century BCE. But ten more copies came out of Cave 4, with further fragments from Cave 5, and they do not agree with it. Some lack the Two Spirits discourse entirely. Some carry a shorter form of the penal code, or a different arrangement of the closing hymn, or omit the passage on the sons of Zadok. Whether the shorter Cave 4 forms are earlier drafts or later abridgements is argued both ways, but the fact underneath is not in doubt: the Rule was rewritten as the community changed. Reading it as a single fixed constitution misdescribes it.
The identification of the community is the larger dispute. Josephus, Philo and Pliny the Elder describe a Jewish group called the Essenes marked by common property, a probationary entry, communal meals, strict purity and celibacy among many members, and Pliny places a settlement of them on the western shore of the Dead Sea. The correspondence with the Rule is close enough that the Essene identification is the majority view. It is not unanimous. Lawrence Schiffman argued from the legal positions in a Qumran halakhic letter that the movement's origins are Sadducean or Zadokite rather than Essene. Norman Golb held that the scrolls are not a sectarian library at all but the contents of Jerusalem libraries hidden during the revolt. Josephus's account also does not match the site cleanly, including on the presence of women.
Parallels with the earliest Christian communities are real and should be stated exactly: a shared purse, a communal meal, an overseer, a governing council, a sense of being the true remnant. They are parallels of organisation between two Jewish renewal movements of the same period and place. No literary dependence in either direction has been demonstrated, and the theologies differ fundamentally.