I think GDPR itself is a bit unclear here. Google Search still operates in Europe as far as I know even though it scrapes and indexes people's websites without explicit consent, and I suspect GDPR doesn't intend to make it illegal to do this. Could be wrong...
IANAL but at least in the U.S. I'm pretty sure publicly-available data is generally excluded from whatever protections do exist on PII. I'm not sure what, if anything, has been said about this in the EU.