It sounds difficult to make a definitive statement based on the findings of the referenced paper:
"Overall, the vitamin content of the frozen commodities was comparable to and occasionally higher than that of their fresh counterparts. β-Carotene, however, was found to decrease drastically in some commodities."
Yes, citation needed (and also probably unlikely to be forthcoming or validated) but the rest of the comment stands, so let's just ignore this weakest/most-dubious claim.
https://www.ncbi.nlm.nih.gov/search/research-news/4060/