By sheer numbers, yes. By impact, no. Ireland's population was halved by death and migration caused by British laisse-faire economic policies - policies discussed and approved in parliament they were supposedly part of and represented by. The famine was also key to the loss of the Irish language and a sense of collective shame and anger that warped the society for a hundred years.
For comparison, the Bengal Famine killed "between 800,000 and 3.8 million" - the lower estimate being significantly small than Ireland's, the upper estimate nearly twice as many. But in the context that Bengal was already at near starvation with "the least nutritious (diet) in the world" by 1930 (Ireland was producing quality, nutritious food even as its people starved), and its population was 63 million people (compared to Ireland's 8 million). The Great/Madras Famine of 1876 killed between 5 and 9 million people - in a local population of 60 million. Horrifying numbers but we're talking states that had more than seven times Ireland's population having deaths of between twice and four times of Ireland's. By impact and by its ease of prevention, Irelands is not "small change". Frankly in a comparison of 2 million dead Irish vs 2 million dead Bengalis vs 7 million million dead south Indians, nobody is "small change" even outside of context.
Ireland's population didn't start going back up again until 1963. It has yet to recover to pre-famine population. Comparing famines is a shitty thing to do, but at least do it fairly.
There are lots of good articles online, but to provide a non-AI summary:
language was already declining in cities before the famine, for a few reasons: social mobility (your employer and your neighbour with books and tea parties didn't speak any Irish), education (schooling was in English; schools were run by both the British government and Irish Catholic Church but at this time (and for many years hereafter) the Catholic Church was an ally of British imperialism in Ireland, seeing nationalism as a distraction from religious rights within a united kingdom - to many, they believed the UK was just waiting to return to Catholicism and Ireland being in it would provide Catholic pretenders a home base); emigration (even before the famine, there was a degree of emigration (and lesser famines...). Knowledge of English was key to securing work in America and other colonies, or even just in Britain. Taking English-language school was therefore key even if you just wanted out. By the time of the Famine, Irish-exclusive speakers made up 28% of the country - not a majority by any means but drastically different from today.
the Famine primarily affected rural communities. Of those 28%, almost every single one lived in rural, western Ireland (the same places that primarily retain the few thousands of real Irish-first people today, excluding the recent boom in city-focused language revival). The land was essentially cleared of people, who either died, emigrated, or moved to cities for work, charity or, indeed, to prisons. Quite apart from just a smashing of any network effect where the more speakers a language has, the more will learn it, it also split families, split local dialects (a Munster Irish speaker is only by some degree better able to understand Ulster Irish than Scottish Gaelic), and massively reinforced the existing factors in the move to English speaking: employment and integration with those that weren't suffering, the Anglo-Irish or direct English imperialist.
the Famine afterwards came with a high degree of shame. Stories of eating grass, eating pets, eating pests; of stealing from each other; and even stories of cannibalism. Since the English declared that the Famine was God's Providence (a handy excuse not to interfere), many looked at the native Irish as deserving their plight. The Irish native identity - including the language - became shameful and something to be downplayed and distanced from. Now, from this low point, there was a revival and new pride and nationalism that arose. But it was created in English, by people who now spoke English, and aided by many Anglo-Irish people who saw governance of Ireland by Ireland as less of a blood right and more of a practical and moral matter.