For Form 8615 I am being asked "Was your earned income more than half your support in 2023?" and am unsure how to answer. Around 95% of my "support" came from my earned income of $17,425, the $2,641 from my 401(k) cash out used for school, and the rest from graduate student loans (which were roughly $45,000). Very little of my "support" came from my parents (roughly $1,500). Do I answer yes or no to "Was your earned income more than half your support in 2023?"
Q. Do I answer yes or no to "Was your earned income more than half your support in 2023?"
A. You answer No.
Your statement "Around 95% of my "support" came from my earned income of $17,425, the $2,641 from my 401(k) cash out used for school, and the rest from graduate student loans (which were roughly $45,000)" is a little confusing. Student loans and 401k cash outs are not earned income. You apparently spent $65,066 (45,000 + 2641 +17,425) on support last year (tuition is support). Only $17,425 came from earned income (working), and that is less than half.
The "kiddie tax" (form 8615) although based on your parent's tax rate, is not conditioned on them supporting you. Full time students, under 24, are subject to the kiddie tax, if they don't support themselves by working, whether the parents are involved or not. Why? The rationale is that loans and your own savings are just an alternative to parental support. Note that only a portion of the $2641 will be subject to the higher tax rate; none of the $17,425 will be.
An aside: using a 401k for education is not an exception the the 10% early distribution penalty. That exception applies only to IRAs.