score:5
IRA bombings did increase Hibernophobia in Great Britain, as one would expect.
John O'Beirne Ranelagh's "A Short History of Ireland" (Third Edition, Cambridge University Press, 2012. Page 217) makes mention of increased Hibernophobia being a result of IRA bombings during the lead-up to World War II:
The effect of the IRA bombings was in Britain to alienate public opinion completely and encourage Hibernophobia [...]
Though, of course, the IRA could hardly be blamed for originating Hibernophobia, as some degree of Hibernophobia existed at least as far back as the 1100's, when King Henry II's son, John, wrote of the Irish:
Dedicated only to leisure and laziness, this is a truly barbarous people. They depend on animals for their livelihood and they live like animals.
(Gerald of Wales, Giraldus, John Joseph O'Meara. "The History and Topography of Ireland". Penguin Classics, 1982. Page 102.)
Hibernophobia has been so pervasive in English culture, that even supporters of the treaty that created the Irish Free State indulged in anti-Irish racism. (Paul McMahon. "British Spies and Irish Rebels: British Intelligence and Ireland, 1916-1945". The Boydell Press, 1988. Page 171.)
All that being said, I'm not aware of any studies or books written specifically addressing the issue of the prevalence Hibernophobia in response to The Troubles. It seems rather like asking if Islamist terrorism has increased Islamophobia, or if the Civil War and reconstruction inflamed racist sentiment against African Americans in the United States. It's just taken as a given. Everything I've seen on the topic has approached it from the stance of debunking the idea that the IRA caused Hibernophobia, such as "Religion, Class, and Identity: The State, the Catholic Church, and the Education of the Irish in Britain" by Mary J. Hickman, which was referenced at the time by a UK paper under the subtitle "Anti-Irish racism is as old as the 12th century: it is not the result of IRA terrorism, says a study published yesterday."