At lot of the special one-per-universe buildings are that way. They get no personal benefit from adjacency, and their benefit of having is the big bonus thing they provide, plus the adjacencies they GIVE.
It does seem reasonable.
On the other hand, a non-trivial number of the "one per civilization" buildings are somewhat broken in a parallel manner: they aren't the kind of improvement that they give adjacency bonuses for, so while they might get leveling bonuses themselves, they seldom do. That is, the building is of type "Influence", but it only gives "Research" adjacency bonuses. Since these buildings tend to be natural "hub" buildings, not getting back the adjacency benefit they give means they themselves seldom have few levels.