I agree. Hosts should do things like not operate in areas where zoning or other ordinances prohibit or require regulatory compliance for this type of activity. If hosts were operating as an actual lodging establishment, the existing legal framework would provide a solution to discrimination issues.
If Marriott tried to put a hotel in the middle of my neighborhood, which is an 2-4 family residential zone, that effort would fail. If you tried to open a conventional B&B, (there was one that operated about 6 blocks away for many years) you would need to meet certain safety standards like having appropriate fire egress (ie. fire escapes, alarms, possibly sprinklers), have appropriate parking, allow neighbors to react and provide perspective, etc.
In the case of that B&B that was in my neighborhood, they had to install fire escapes, and the neighbors requested that a fence be installed to prevent guests from using their lawn as a pathway.
Renting out a room to another housemate is a very different thing to listing a room for a nightly rate as a commercial transaction.
Whether that automatically means you should be governed by the same laws as a hotel is unclear, but asking whether it might be appropriate is a really important thing to do. The rules society created for hotels weren't just randomly invented rules - we wrote those laws for what we considered very good reasons to prevent certain kinds of discrimination that was actually happening and the we decided was wrong. I think there's a _very_ high chance that Airbnb hosts probably should be held to those same rules or something very similar but less directly aimed at hotels.