> Like every year, I decided to travel to FOSDEM by car. It is not the most relaxed option, but it comes with one very important advantage: arriving early enough to secure a parking spot directly on campus. That also means the journey starts very early in the morning, long before the city fully wakes up.

Curiously backwards. That's one way of reframing a disadvantage as an advantage. The train connection seems to be 3h15m to 3h30m from Neuss train station to FOSDEM. A single connection for the long-distance train in Cologne, the rest is local public transport within Brussels.

(The OP may been /s without me realizing.)