I can agree with you that players matters the most in a club but let us be honest, there is importance of having a good manager. You cant come and write out mangers as if they dont play an important role in the team success. Most players dont play to their full potential because they are not giving the necessary tutorials but when a good manager understand all the players in his team. He knows the best formation, position, inversion to carry out. Managers contribute to the success of the team and we should acknowledge that.
It is clear that everyone must admit that when a team is handled by a coach who understands the players in it, of course he will know what formation to apply and also know how to place certain players in which positions. So the team can be stronger than we imagine and that has really been seen in PSG last season where Luis Enrique has really succeeded in changing the PSG team that previously looked ordinary into a team that is quite strong in the Champions League and also in its own domestic league. So the contribution of the coach must clearly be considered important in a team besides the players who do have their own potential with their performances.