I totally agree with your statement, Real Madrid might win, but they have little chance of making it to the semifinals. Their task this time is very difficult, they must score at least three goals to force Arsenal to continue the match into extra time.
Yes, Arsenal cannot play defensively because Madrid attack is very dangerous. Arteta must not take risks in the second leg, Arsenal must be able to match Madrid game if they do not want to lose their chance to advance to the semifinals.
If Arsenal play aggressively like they did in the first leg, I think it could be a disaster for Arsenal because Real Madrid's counterattacks will definitely be quite deadly in this second leg. Because with an aggregate of three goals, Arsenal still has to consider Real Madrid as a very dangerous team in the Champions League because if Arsenal immediately underestimates Real Madrid in this second leg, it could cause Arsenal to regret it. I also don't see Real Madrid qualifying more easily because when the match is going on, the main thing that Real Madrid has to think about is equalizing the aggregate so that they can have another chance in extra time.
Arsenal are already 3-0 ahead of Real Madrid, so Arsenal don't need to attack much in the second leg match, but it would be wise for them to play defensively against Real Madrid and prevent the attacks of the opponent's players in the midfield position. Real Madrid is a very strong team at home, so if Arsenal makes a mistake and scores more goals to secure the next round with a big margin against Real Madrid, then this will definitely be a mistake for Arsenal. As far as we understand from the outside, maybe all the staff and managers of the team understand this better from being close to the team, so I think Arsenal will finish the second leg match against Real Madrid with a good performance.
It seems that a great opportunity awaits Arsenal now, as they have the potential to surpass their traditional club at this point. We don't know what Arsenal and Real Madrid's game plans are for the upcoming match, but it's safe to assume that Arsenal will try to be much stronger in defense. If they can get their defence right against Real Madrid, I think Arsenal can definitely qualify for the semi-finals. We still see that many people are giving Real Madrid the highest priority for the second leg match, and even according to Google, they are ahead.However, it can be said with confidence that Arsenal will be able to move forward in a much more refreshed manner, proving all the speculation to be true.