First, are you saying that the early Reformers did not look at historical Christianity for its foundation? If so, you are uninformed of what they wrote.
Second, thank you for the tacit admission that the RCC in its current form started in 1054.
The Orthodox Church is more divorced from pre-1054 roots than the current RCC.
The early Reformatters selectively looked at historical Christianity.
They completely skipped the early heresies and that’s why many repeated them.
As to knowledge of the early church - that is sorely lacking among the non-Catholic/Orthodox groups