LiFePo are a retro step for Evs.
They may have advantages in cycle life , but certainly lose out on specific energy, and volumetric energy.
I doubt there is much cost difference either way, in terms of $/kWh if production volumes are similar.
.. And if Tesla really can make a “million mile” NMC/NCA/etc cell, cheaper still,.. then there is little advantage for LiFePo.
Most “end users” (EV buyers) probably dont understand or care about cell chemistry, pack size, weight ,cycle life, etc
What they will care about is initial cost, safety (fire risk), vehicle driving range, and possibly recharge time.,
To optimise those parameters will likely require some other improvement or a new chemistry.