I've noticed that trades are down too. It's probably a case of us not being able to have it both ways. In most of the previous versions, the complaint seemed to always be that there were too many trades, so I guess Markus or another one of the OOTP developers decided to make a change and turn it down, hoping to satisfy those that complained that there were too many. See
here for somebody who thinks he's getting too many trade offers in OOTP19. What are the developers supposed to do? You can see the conundrum. You can't please everyone. Try different settings and see what works for you. When I used the "low" setting in a 40-year test sim, I wound up with slightly over 200 trades in total, which is a little over 5 per season, so I will be adjusting upward. Like BBGiovanni, I don't enjoy seeing some of the ridiculousness that can come with that ("Manny Machado for Matt Reynolds and a hot dog vendor" - LOL!), but it appears I will have to adjust upward for this version. I'll go to average first, and check out how it does over the first ten seasons, and adjust from there.