"You can use your modified AGI from the year you take delivery of the vehicle or the year before, whichever is less. If your modified AGI is below the threshold in 1 of the 2 years, you can claim the credit."
https://www.irs.gov/credits-deductions/credits-for-new-clean-vehicles-purchased-in-2023-or-after

I found my mistake.  If you don't enter an amount in the 2022 AGI box, then Lacerte assumes it was zero and allows a 2023 credit regardless of the AGI.  This needs a programming fix.  Hope they take care of that in 2024 Lacerte.

I'm curious how Lacerte would 'know' the prior year AGI if you didn't use it to prepare the prior year return?

There's a field to enter it. I'm guessing this is something that didn't proforma, because the proforma program was essentially complete before anyone realized it was necessary.