This is incorrect.

non-refundable credits reduce your tax liability still. Just because the big number on TurboTax is a green $1 refund before the EV credit, doesn’t mean you won’t get $7500.
The credit reduces your liability by $7500 until your liability would be $0.

In your example, if someone is earning something like $100k+ per year, they’re probably paying more than $7.5k in taxes that year (because their marginal tax rate is higher than 7.5%). You don’t have to try to owe $7.5k at the end of the year to get the credit.

Most low mid to high earners will get the full $7.5k back if they don’t exceed the credit income threshold.

source: I’m not a tax professional but I bought an EV

unless this is what you meant…. Tax discussions can get very confusing because it requires very precise language.