Okay cool. Within Brussels it's sorta fine indeed, I guess I'm biased by the commuter view ;) Within the city it's definitely getting better the last few years.

The main policy issue is for sure the cars for pay... Some politicians wanted to abolish it since years, but it only grows year after year. Recently they made it only tax-friendly for electric cars, saying the system must stay because it helps transition to electric cars faster (I think that transition would happen very fast anyhow and I think transitioning to (e-)bicycles is better). Understandably, people who currently have such a "free" car from work don't want to give it up (and that's a lot of voters), as they also use it to go on holiday with the family and such.

A main infrastructure issue is the tunnel (you probably travelled in it) running north to south. So many different trains in Belgium get squozen in the same little piece Brussels North - Central - Brussels South, the tunnel is very saturated, and messy with highspeed, intercity, local and S trains all going there. It just needs 1 little incident and plenty of trains all over the country get delayed.