It really isn't. That is just not true at all. I mean, have you only just started watching football? Nearly every league winner and most top 4 finishers each season are built on a tight defence. Leicester basically won the league by grinding out 1 nil wins most weeks, it was their defence and Kante (DM) that won them the league, and Vardy/Mahrez nicking goals. Woolwich have challenged by having a tight defence. Look at Liverpools defence this season. Best in the league and they sit top. City's success was built on defence and suffocatign teams and letting their attack destroy teams. Now City have been struggling, guess why? Because their defence fell apart and they started conceding goals.
Positions are rarely decided on goal difference let alone goals scored. .Teams that win things are almost always built on a tight defence. Hence why if we are controlling games and rarely concede, you always have a chance in games.
Our defence gave us the platform to win last night, we defended well, kept a clean sheet and scored one goal, and voila we won. If we had kep a clean sheet against Newvastle, we'd have won. We conceded two goals and lost. That win last night doesn't happen if you are conceding multiple goals every game as we have found. Just look at our recent results under Ange, conceding at least 2 goals a game and we've basically lost every game despite scoring in every game too.
If you are constantly conceding goals, and then you have a period where your attack is misfiring, as a team you are fucked. You will lose lots of matches.
So what you are saying is just plainly not true if you want to be a successful team. It's about getting your defence tight, to give you a platform to score goals and win games. Of course the more you score, the better, but not at the cost of your defence. It's football 101 and nobody is successful conceding lots of goals over a league campaign no matter how many you score.
To say that being involved in high scoring games each week is preferable to having a tight defence and being able to grind out wins 1-0 when not at your best, is just laughable.