"considered unproductive" is correct and usable in written English.
You can use it to describe an activity that is viewed as inefficient or ineffective. For example, "The company made the decision to stop investing in the project, considering it unproductive."
So is anything actually considered unproductive nowadays?
Monitoring and Taylor-type assembly lines are considered unproductive.
State-backed research since the 1970s has turned the Cerrado — once considered unproductive scrubland — into a vast farm belt.
But in the United States, to doze, to snooze, to wink or to indulge in a few zzzzzzz's is considered unproductive, if not unseemly.
Shrubs take up about 1 million ha and most of this land could be considered unproductive and constitutes one of the main sources for initiating forest fires that devastate more than 40,000 ha per year.
Skilled at snooping on Wi-Fi users in cyber cafés and hotels, it uses sophisticated data-mining software that tracks down keywords on search engines such as Baidu, along the way issuing warnings to Web hosts to amend or delete content considered unproductive of "harmony".
The "Conservapedia Commandments" also require edits to be "family-friendly, clean, concise, and without gossip or foul language" and that users make most edits on their site quality edits to articles; accounts that engage in what it considers "unproductive activity, such as 90% talk and only 10% quality edits" may be blocked.
Polls show that almost half of Americans oppose committing any more troops, escalating rather than withdrawing militarily, in what is considered an unproductive and unnecessary entanglement in that impoverished, beleaguered and war-torn country.
Forty percent of the surface is considered as unproductive vegetation, 30% as forest and the rest as residential/agricultural area.
While Sittenfeld says he can "understand people's cynicism about politics," he considers it unproductive.
These are parcels that commercial farmers may have considered to be unproductive or unusable.
