This peer reviewed 2022 study from the Cancers journal shows that while sunscreen should always be worn, highly-rated UPF clothing should be considered your first line of defence for UV protection.
Slip versus Slop: A Head-to-Head Comparison of UV-Protective Clothing to Sunscreen
https://www.mdpi.com/2072-6694/14/3/542
This 2020 review paper from the Journal of Photochemistry and Photobiology summarised the availability of sun-safe hats during a three-day cross-sectional survey in a large Australian shopping mall.
It found that of the 524 hats examined, 69% did not meet the Australian & New Zealand government standard (AS/NZS 4399:2017). 9% of the hats claimed to be UPF 50, but about half of these were not sun safe.
Availability of Hats That Meet Australian Sun-safety Standards at a Major Canberra Shopping Complex