A while ago I asked what was the reason since the sun wasn't even up and my TCAS was showing nobody in my way
Sun is not a factor.
Your TCAS shows only the present situation. You know where the surrounding traffic is, but you don't know where it goes.(here, I could come back to language and comprehension of the situation)
Sometimes, you have to descend early just in order to land on your destination, but you can't see that on your TCAS.
Let me give you an example :
Planes going to Paris CDG via ANG have to be there FL 280 (which is quite low) 50 miles too soon, I guess.
First reason : Paris has to sequence them ASAP. Being at FL 280 gives them a chance to fly IAS and except some "big machines", most of the traffic becomes "compatible".
Second reason : if they are not at that level, they enter another sector dealing with London's and Paris' departures. By definition, if he's not below, he's above. A bit harder to deal with, but why not.
So the plane, instead of being below, has to cross 5 different flows in a sector that didn't even waited him...Why not. Let's say he was awaited.
Now, he's above departures from London and Paris, AND arrivals to Brussels let's start the descent... "be level in 3 min"/"unable"... "Roger, radar..." .... OOPs a bit late, now. Here come the departures from Brussels, Franckfurt, Luxemburg, there's another departure flow from London... and the arrival to Paris is still up high above everybody, where (not when) it should be established on final...
Maybe a rerouting via Hamsterdam will be the solution.
This exemple is a bit long, but it represents a 6 minutes' situation, around 50 miles... The distance you wanted to save.
Nothing to do with friendliness. But a bit of cooperation can, indeed, help. Procedures have been thought about by far better controlers than I am.