'merely restricted' is correct and usable in written English.
It typically implies that something is limited or confined to a specific degree. For example, you might say "The defendant was merely restricted to a two-year sentence."
Watching rugby should be fun and not merely restricted to diehard fans with decent incomes.
They just gave stress tests to the biggest banks, and merely restricted the bank from paying out a dividend.
Figures of the first few nodal patterns are drawn: they are quite distinctive and not all merely restricted to regular rectilinear sub-divisions.
The reluctance to allow any managerial speculation to accumulate is not merely restricted to transfers – where Newcastle are showing a healthy profit this summer – but extends to infrastructure.
The Fourteenth Amendment merely restricted the freedom theretofore possessed by the States in the making and the enforcement of their criminal laws.
There are plenty of other stories of that nature and, if nothing else, at least the revulsion of Blackpool's fans is not merely restricted to the Fylde coast.
It merely restricts the Treasury Department's ability to pay bills Congress has already incurred.
The INF Treaty was the first arms-control pact to require an actual reduction in nuclear arsenals rather than merely restricting their proliferation.
It merely restricts one person, the assignor, from denying that he sold a patent when he purported to sell it, leaving the whole rest of the world free to assail the validity or novelty of the patent.
Tom Miller, the Iowa attorney general, who was by far the most active of the 19 attorneys general, said the idea "was somewhere between conduct and structural" -- that is, between merely restricting Microsoft's behavior and actually restructuring the company.
Accordingly, from a cosmopolitian perspective, the borders of states merely restrict the scope of justice and are irrelevant obstacles to appreciating and acting on one's responsibilities to everyone in the global community.
