The batteries don't live in isolation. There are other pieces that are dependent, whether for basic function or for calibration.
Example: Chevy issued a recall for mislabeling some Bolts as N2.1 vs N2.2. The fix is a sharpie to fix the label, and "reprogramming the Hybrid Powertrain Control Module 2". I could find no information on either of these chemistries. Dropping in a LiFePO4 would require at least the same, and possibly more.
Now, if you're suggesting simply swapping a matching replacement part (obsolete as it might be), then I'm on board with that