But to answer your four questions, none of those things are racist. Two of them are discriminatory, one is addressed directly in the article and the last one is plain and simply concerning, but it's not racist.
Again, not defending them, just recontextualizing. You're doing exactly what the OP is calling out: Painting everything as racist rather than attack the actual issues. This is how we got in this mess.
http://www.independent.co.uk/news/world/americas/donald-trum...
It is against all principles that America is founded on. It is utter bigotry and yet it is happening.
At the core of these issues you'll find people who are being sold solutions to a problem they personally have, regardless of the problem being valid. Labeling those issues and people as racist does nothing to help, and it's certainly not a solution. Especially when the labeling is wrong - I know a lot of trump supporters who want nothing to do with any of the discriminatory bullshit, yet people call them racist as soon as they speak out. This is a real problem, it's not something that's happening to a couple of guys out of 300 millions.
How is discrimination based on race not racist?
Students house-sharing at universities.
Online dating.