One theory is that yellow-green wavelengths don't pass through water as readily, hence ancestral sea-dwelling plants adapted to absorb red and blue wavelengths

One theory is that yellow-green wavelengths don't pass through water as readily, hence ancestral sea-dwelling plants adapted to absorb red and blue wavelengths and that adaptation remains "good enough" for contemporary land plants. Highly recommend the book "How the Earth Turned Green" https://press.uchicago.edu/ucp/books/book/chicago/H/bo16465693.html https://press.uchicago.edu/ucp/books/book/chicago/H/bo164656...