Epitaphs were not banned in Colonial New England, but permanent grave markers were uncommon prior to 1670, making epitaphs by extension rare. I can't speak to this exact marker, but here's a more general explanation of burial and memorialization in Colonial New England.

Burying grounds in Colonial New England were unconsecrated, town owned spaces. This was a Puritan rejection of the traditions of the Catholic Church and the Church of England, where burial spaces were sacred and the burial process a deeply religious affair. In New England, in the Puritan tradition, funerals were not held in churches, burials were silent, and ministers would not be present for them. This reflects the Puritan belief in predestination, that God picked who would go to heaven at the beginning of time. Stone grave markers, at least in the first half of the 1600's, were seen as too Popish by these early Puritans. Gravestones become much more common in the 1670's and 80's, which is where you start to see those famous death heads, hourglasses, and cherubs associated with New England gravestone art. It's possible that earlier graves were marked with wood or other simple, non permanent materials. The shift in the 1670's could be attributed to Rev. Samuel Mather, brother of Increase and Uncle of Cotton Mather, who makes the case in a 1672 treatise that stone markers were not idolatrous, and therefore acceptable among Puritans and non-conformists.

Source: Caitlin G.D. Hopkins "The Shadow of Change: Politics and Memory in New England's Historic Burying Grounds, 1630-1776" https://dash.harvard.edu/handle/1/12274107