Interesting, but hard to see how the NCAA could ban a school from non-specific school advertising anywhere it wants to advertise. It would certainly not stand up in court.
NCAA is not the government and has no obligation to guarantee free speech. As a private organization, it can regulate the speech of its member institutions if they want to stay members, and it does so all the time by telling them how and when they can talk to recruits.
If they violate its rules, it can impose very expensive sanctions including loss of post-season play, and worse. You don't often see universities, no matter how well-heeled, litigating over recruiting violations. One reason is that as college sports are currently structured, the members need the NCAA and can't afford to become members in bad standing or non-members. For another reason, the vast majority of individuals and institutions that sue the NCAA lose. There is a tendency of the courts to uphold regulations adopted by administrative authorities unless those regulations are clearly arbitrary and unreasonable.
Now, if NCAA adopts rules that are
unreasonable, and enough members agree on that, the rules can be reformed by pressure from within. And successful, or favorably settled, lawsuits become possible. One avenue is to allege an unreasonable restraint of trade, a violation of the antitrust laws. Another is to allege breach of contract, covenant of fair dealing, etc. based on what the institution was signing on for (i.e.
reasonable regulation) when it agreed to abide by the Constitution and By-Laws of the NCAA.
So I think an NCAA rule against targeting particular recruits with advertising would be bulletproof. The key will be to distinguish targeting from general advertising of the program. As with any rules, there will be gray areas, and the rules will need to establish reasonable factors and criteria for identifying what is forbidden.
I certainly don't think the argument that a school can engage in "non-specific school advertising anywhere it wants" has a prayer of succeeding under a reasonably focused NCAA rule or in a court challenge of that rule when you're talking about a unique billboard on the road between a recruit's home and her high school.