It was a huge win for Liverpool and I feel sorry for Arsenal for their early exit from the tournament. Arsenal are lacking a good stricker and they need to get that settle immediately if they are to change their fortune anytime soon.
For me, it is not a big win but it is surely an important win. Liverpool only scored 2 goals during the match, they also actually didn't dominate the match. However, they are lucky that they could score 2 goals in the match. Arsenal more dominated the match, they created more chances in scoring goals. But Arsenal fails to score a single goal, we can assume Arsenal players has lack of accuracy in shooting. If they have good accuracy, Arsenal may score many goal during the match.
In my own opinion, I think it was an important win and also a big win for Liverpool because it's actually not easy to beat a strong English Premier League club like Arsenal. It was a very difficult game for both sides as the two clubs searched for a win in the game but it was Liverpool who first found the net after Arsenal player scored an own goal.
I think it was game that Liverpool were destined to win if you ask me because had Arsenal converted their own chances, the result of the game might have been different from what we saw today. Liverpool have successfully eliminated Arsenal from the English FA Cup and have progressed to the next round of the competitive.