Re contemporary symphonies, I have a list of what I consider the greatest symphonies from the beginning (c 1760) to now. Of course it is biased by my biases (almost no Romantics except Bruckner), but I was amazed when I put these symphonies on a timeline to find that besides the 1760-90 period the most crowded period is in fact 1939-90. I’m sure that the drop off after 1990 is mainly the difficulty of finding out about recent and contemporary performances, and the reluctance of record companies to record contemporary classical music that is symphonic (or string quartetic) rather than gimmicky.