If you read the classified ads for rentals in Oregon, you’ll see a lot of “No Section 8” warnings. It’s pretty common, especially in Portland.
This new law will explicitly prohibit that practice.
The will quite likely be an exemption for those who possess less than 3 or 5 units. At least last time I looked, FED fair housing law had the same thing, though they don’t mention it when they are advertising about non-discrimination...