As a rule of thumb, I will gladly pass on Tor traffic, but no exit node, and I understand if network admins want to block entry node, too. It is a decision everyone who maintains a network has to make themselves.
The reason I block it is also the same reason I block banana republics like CN and RU: these don't prosecute people who break the law with regards to hacking. Why should one accept unrestricted traffic from these?
In the end, the open internet was once a TAZ [1] and unfortunately with the commercialization of the internet together with massive changes in geopolitics the ship sailed.
[1] https://en.m.wikipedia.org/wiki/Temporary_Autonomous_Zone