Datums isn’t the problem as it’s correctly pluralized in the context of the jargon because they are two different types of datums. The problem is that expanding the acronym breaks the sentence, “But the North American Datum of 1983 and the North American Vertical Datum of 1988 datums are getting replaced soon.” It’s redundant, like saying ATM machine.

I think it’s fine.

https://www.merriam-webster.com/dictionary/datums

1: plural data ˈdā-tə  ˈda-

also

ˈdä-  : something given or admitted especially as a basis for reasoning or inference

an important historical datum

This enormous expense—and considerable risk—to pick up a datum or two about geriatrics?—

Charles Krauthammer

2: plural datums, mathematics : something used as a basis for calculating or measuring

measuring the distance between datum points

… make things more efficient for those of us whose work requires a time datum.—

Robert Steinbrunn