If we are talking about Atletico Madrid's chance to win a Champions League title, then I don't think it will happen in the near future. 
While Real Madrid is getting Mbappe and there is a Manchester City fact too, it is really not easy to reach the title. Besides Atletico Madrid's lowest expectation in this tournament isn't winning the title. Even a quarter finals qualification is seen as good achievement.
The board are really contented with the way Simeone is managing the team. They even extended his contract not much time ago. Would he like to achieve a Champions League title? Who wouldn't?
But Atletico Madrid need to make a huge improvement to reach even the finale once again (The last time they did it was the 2015/2016 season).
Atletico Madrid played in the 2014 and 2016 final of the UEFA Champions League competition which was the close to times they almost won the the UEFA Champions League title but unfortunately for them, it was their biggest city rivals Real Madrid that they had to face in those finals of which they were beaten. Currently, I don't think they have the squad that's strong enough to challenge for the title and despite their struggles in recent seasons they've always decided to stick with their manager Diego Simeone. While Real Madrid is getting Mbappe and there is a Manchester City fact too, it is really not easy to reach the title. Besides Atletico Madrid's lowest expectation in this tournament isn't winning the title. Even a quarter finals qualification is seen as good achievement.The board are really contented with the way Simeone is managing the team. They even extended his contract not much time ago. Would he like to achieve a Champions League title? Who wouldn't?
But Atletico Madrid need to make a huge improvement to reach even the finale once again (The last time they did it was the 2015/2016 season).With the club under Diego Simeone, I don't think they are going to be a major contender for the UEFA Champions League competition anytime soon because it's still the same tactical approaches he's adopted in recent years that he'll continue to maintain.