IANAL but I don't think it matters whether the purpose of collection is specifically to facilitate paid features. From the European Commission:

> The GDPR applies to: [...] > 2. a company established outside the EU and is offering goods/services (paid or for free) or is monitoring the behaviour of individuals in the EU.

Assuming account names or the content of comments constitute personal data within GDPR, I think YCombinator falls into this group.

Edit: I forgot HN collects an optional email address too, which is definitely personal data.

Details here: https://www.ycombinator.com/legal/#:~:text=Hacker%20News%20I...

The GDPR applies to the data of people residing in the EU. The location and profitability of the organization collecting the data isn’t a factor. (Though it may introduce questions of enforcement.)