It seems that spending money to buy a star player is not their style in every transfer exchange. Diego Simeone released more star players than buying it, let's say Griezmann who was released to Barcelona even though Barca was their own competitor in La Liga and then bought it back from Barca after the price dropped. Seeing Atletico's style on the Tranfer Exchange is almost similar to the style of one of the Bundesliga Borussia Dortmund clubs who like to sell players to rival clubs Munchen.
Atletico Madrid also have some habits of expensive transfers, but I believe they have a good business strategy when it comes to player transfers. Their record for the most expensive transfer ever was when they signed João Félix from Benfica for €127.20m.
But you can find out some others about their transfer record at this: Transfer record in Atletico Madrid.
The dominance of Real Madrid and Barcelona does look firmer, naturally because the two clubs have a lot of money to buy star players. But a little mistaken if many call Atletico as a complementary club and favorite of the top four La Liga standings because when viewed from the statistics of achievement in the last decade they have also won La Liga twice in 2014 and 2021.
Atletico Madrid are title contenders instead of just Barcelona and Real Madrid. I agree about that.