Is there a link to the study in English. A newspaper with one quote does not make a study.
Islam is a virulently violent ideology and political system. Whereas the OT is rooted in history and appears to speak of violence is a past tense - the Muslim tests have a very here and now feel to it. There will be blood aka End Days which is what the hadith and Koranic literature is awash with. Not to mention that it obsesses with the afterlife and its eternal punishment.
I would have to say that the only way I could qualify this is if she separated the Old Testament/Injil bits out of the Quran. Those references to Allah's previous temper tantrums would be common to three religions, not one, and would not be new ideas specific to Islam. Regurgitating another religion's violent history shouldn't count.
I find it really hard to believe that the OT was less violent than Quran. That book horrified me as a child.
It is a mistake to treat the OT as history since a number of events have no historical merit. However it fine as a theological narrative which has some history behind it.
If you look at a number of the horrible events in the OT many of these are God's Will not commands as per the Quran. Judges 7:2-3 has God commanding the Israelites to disband a majority of their army so victory is by God's Will rather than the believer's acts. This strictly puts the believer as a puppet/tool rather than an independent being which is enforcing a command as a choice and thus free-will. If you read the full chapter God hand picks which men are to fight reducing the army from 30,000 to 300 men. Those that fought acknowledged the suspension of their rights of "being" as tools. Joshua 5:13-14 likewise has the believer function as a direct tool of God's Will while making the ground Holy. For a place to be Holy is recognize Divine Presence at a location. This is different from a synagogue which only some are considered Holy. Joshua 6 and Joshua 10 shows God's Will not the actions of the believers delivered victory. Besides God's Will as an act on the believer tool these verses also show God's Will upon the unbeliever. Leviticus 19:33-34 is a command not an act of God's Will, I mention this to provide a distinction between God's Will and God's Command.
So we have a theological distinction between a descriptive events and a prescriptive command using the previous verses. While the Quran has distinctions between believer and non-believer as political commands. The Quran has a greater emphasis on commands rather than God's Will when it comes to questionable treatment of non-believers. This is a direct contradiction to the idea of the Hebrews as the Light of God, representatives of God's Commands and Will as per above. Unequal treatment between a non-believer and believer in the Commands which dictate political and social concepts would cast a shadow on the Light, Numbers 15:15-16, Leviticus 24:22, Exodus 23:9, Deuteronomy 24, Deuteronomy 10:18, Leviticus 19:33-34, Exodus 12:48-49, Isaiah 42:6, Isaiah 56:7, Isaiah 66:19, Isaiah 49:6. Also keep in mind the OT is a sequence of events over centuries while the Quran is only of a few decades. So we have a chain of narrations in the OT which theological narratives develop the concept of God's Will within the world separate from the God's Commandments. While the Quran being the last within the chain of prophets can only allow one to infer a victory, defeat, plight, etc, as an act of God's Will. This lacks theological authority which allows anyone to claim God's Will, from peaceful to violent. The issue I see is the some of the Quran's verses which are applied to social and political are based on misinterpreting Commands with Will statements. Both the OT, Romans 15, and NT state God loves the unbeliever, while the Quran has many harsh words for the unbeliever, even one that is peacefully co-existing within a Muslim community. The NT itself is about unconditional love which is built upon the OT. The Quran is the direct opposite with it's unequal treatment between believers and unbeliever in which love is conditional. Allowing different court systems based on religious divides is unequal treatment and contradicts the OT. Commandments which form political and social structures are material. Such structures are used to developed the spiritual connection with God only. The material has no value outside of acts which lead to spiritual development. By placing Muslims at the top of the political structure the Qur'an is expressing material favoritism. This is further reinforce by a distinction under Islamic law between Freeman and Slave; rights, punishments, etc.
Topic: linguist concludes: Islam is the most violent religion.