Who gives a ****? The point is this was passed on "national security" concerns. I am asking what those could possibly be.
Anyone who has lived in Ukraine is well aware of the ingredients. It is a bit complex. However, I will attempt to briefly explain what has occurred.
During its many decades as a part of the Soviet empire (Ukrainian SSR), Moscow did everything in its power to minimize the Ukrainian language and culture. All official documents and publications were in the Russian language. With the dissolution of the Soviet Union and Ukrainian national independence in 1991, Ukraine endeavored to rescue the Ukrainian language and culture. It proved difficult however, to move away from Soviet/Russian modalities that had ruled for 70 years.
Ukraine has had laws governing cinema, copyright, licensing, and broadcasting since 1996. These laws were further updated in 2006. The intent of the 2006 amendments was to create an environment in which Ukrainian cinema, television (and language) could better flourish. The state wanted to increase the share of Ukrainian-language film and television broadcasts from 3% to 25%. There the matter rested quietly until 2014.
After Russia invaded Crimea and Donbas (eastern Ukraine) in the spring of 2014, a social movement in Ukraine - Vidsich (Rebuff) - initiated a "Do not buy Russian goods!" campaign. This boycott even extended to sex, with Ukrainian females wearing t-shirts saying "I will not sleep with a Russian". One glaring humiliation at this time was that roughly 40-80% of Ukrainian cinema and television material was of Russian origin. Ukrainians in the invaded Donbas region (Donetsk/Luhansk) were receiving only broadcasts from nearby Russia. It was precisely at this time that the Russian propaganda facet of their "hybrid warfare" doctrine being used against Ukraine was ratcheted up into high-gear.
This was all too much for Vidsich which began a campaign to limit Russia's penetration of Ukraine's movie houses and television broadcasts. In sympathy, on 11 April 2014 movie theaters in Kyiv, Lviv, and Odessa announced that they will no longer show Russian films. The largest Russian-content broadcasting TV channel "Ukrayina" — contained 87% Russian content. The TV channel "NTN" (71%), "Inter" (67%), "ICTV" (43%), "2+2" (42%). Activists began to hold protests at television stations. The Verkhovna Rada (Ukraine parliament) also took issue with much of the content arriving from Russia... such as the glorification of Putin, the glorification of Russia's security services and military personnel, Moscow chest-thumping over stealing Crimea, and outright propaganda to stir-up rebellion in eastern Ukraine. To make matters worse, Putin cinema/media moguls were receiving broadcasting fees and royalties to distribute and broadcast material slanderous of Ukraine. Vidsich (the people) and the Rada (parliamentarians) were on the same page.
The recently passed (29 March 2016) third reading on amendments (#1317) to the Law on Cinematography says that Russian film/television content which contains popularization, agitation, propaganda, and any action of occupation enforcement agencies, armed forces and other armed military or security forces of an occupier is strictly prohibited. The material of ~8 Russian directors is also prohibited because the bulk of their blatantly anti-Ukraine material is intended for the domestic Russian audience.
And there we are. It is not a blanket ban on Russian content, but a ban on Russian propaganda content. As long as Moscow has troops (currently 9,000) in eastern Ukraine and is an occupier (Crimea/Donbas) of Ukrainian territory, Russian propaganda is prohibited in Ukraine. I personally cannot imagine any nation in a state of active war and partially occupied allowing a similar situation to persist.