That is for employment/workers, not housing. Under equal opertunity employment you cannot discriminate agianst someone 40 or over.
For fair housing, you must not discriminate, such as refuse familys with minor children, except in a number of cases,
one being if 80% of the dwellings units must have at least one occupant who is 55 years of age or older and the community is made and operates as a 55+ place.
If it quacks like a duck, if it walks like a duck, maybe, just maybe its a duck. They will still give some political grace saying its jot PC to call him a nazi even if he starts calling tump “mein fuher”, starts preaching mein kampf, and starts building oddly large ovens.