It was more than just “power over the island”; they wanted the land for grazing animals, and didn’t want to deal with an industrialized country growing behind them while they faced off first with France and Spain, and later Germany.
It was absolutely a genocide; Ireland exported potatoes (collected as rents) throughout the famine while the people starved. When Ireland remained neutral in WWII, England asked them, to black out so German bombers couldn’t use the lights of Dublin etc. to aid navigation; Ireland ignored them.
Recommend a movie on Netflix called “Black 47”.