Although the old format seems better, it is obvious that the new format brings excitement. It is exciting when strong teams play each other many times. Otherwise, we were expecting the teams leading the group to match each other. Now we watched the Real Madrid and Borussia Dortmund match. However, we saw this match in the final last year. We saw very high quality this year. I think the new format is better for the audience.
The new format is better than the old group stage format of four teams per group, with two top teams and two average teams in each group, making it extremely tough for the underdog to qualify and allowing the top teams to qualify from group stages early.
This new format eliminates both that and the advantage of being at home. Teams like as Manchester City, PSG, and Real Madrid would have qualified for the competition after three games in the old format, but they are currently struggling to qualify in the new model.