"Your OpenStreetMap server in 120GB" is only 35 characters, out of 80 allowed for the title, so there's plenty of room to be more specific. "Your OpenStreetMap server of Roads in Europe in 120GB" is still only 56/80 and is much more accurate.
My point is that it's not misleading at all (and thus not clickbait). It doesn't tell the full story, for that you'll have to click it. Most titles on HN don't tell the full story. Many of them could be suffixed with "in America", or "for Mac" or something like that. Yet we don't do that either.
"Your OpenStreetMap server in 120GB" is only 35 characters, out of 80 allowed for the title, so there's plenty of room to be more specific. "Your OpenStreetMap server of Roads in Europe in 120GB" is still only 56/80 and is much more accurate.