If you work in a European company that has a web presence and/or collects data, you should be familiar with what is/isn't personal data by now.
I don't blame Americans or others for not knowing this, but the amount of bad takes about the GDPR by Silicon Valley people in particular is so ridiculous. Every single comment section about a GDPR topic on HN has a bunch of Americans talking about how Europe is some backwards, regulatory hellhole, always talking from a position of total ignorance.