b) This is only roads
OSM is global and covers much much more than just roads. As it is this is a clickbait title.
If you want more of its data displayed in client maps, check out http://www.osm2vectortiles.org which is preprocessed data at 50G global. This also has many omissions and as far as I know a limit to detail in terms of your maximum zoom but if roads is all you need this would probably be a much better choice.
"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.
I never said it was clickbait, that was the GP comment. And if you're going to refer to the guidelines:
"Otherwise please use the original title, unless it is misleading or linkbait."
One could make a reasonable case that the title of the source is misleading because it is incomplete, so the additional specificity may be warranted.
1) "You'll never believe what we built in only 120GB of Ram" 2) "This is how much RAM you need to run an OSM server" 3) "10 reasons you need this simple piece of technology in your life"
I agree that this is pretty uninteresting and don't know why it got so many upvotes, but it definitely isn't clickbait.
"Wikipedia in 5MB" = lie "How small do you think this popular encyclopedia can become? The number will blow your mind" = clickbait
But if you're not a map app developer or a user of one of the affected maps, then it's probably not interesting.
That word doesn't mean what you think it means.