Assuming Xavi is still the coach, Barcelona will still be in second position at the end of each season until the club is strong enough to win Laliga, but currently that a new coach has taken over I don't know ifit will be a problem for Barcelona to finish second in the table next season. Flick is a good coach and I believe he will be supported by the management but it might be difficult for them to win Laliga till they have the players that can outsmart Real Madrid.
Olmo is a good player and very young, if he comes to Barcelona it will be an advantage to them because the team will improve in performance. He can play along with Yamal if he is not sold out and their attack will be strong. However, it will take the coach time to strengthen the team to win trophy but with time he can turn Barcelona into a team that use to be a nightmare to Real Madrid.
I think for next season the results will still be the same for Barcelona to be right under Real Madrid and maybe that will happen for quite a long time. The main problem that causes this is the financial support of each club and as long as this is an unresolved obstacle, Barcelona must face that reality.Olmo is a good player and very young, if he comes to Barcelona it will be an advantage to them because the team will improve in performance. He can play along with Yamal if he is not sold out and their attack will be strong. However, it will take the coach time to strengthen the team to win trophy but with time he can turn Barcelona into a team that use to be a nightmare to Real Madrid.
Even though Barcelona has a coach who is rich in experience like Hansi Flick, in reality it hasn't changed at all, but I hope that at every El Clasico meeting, Barcelona will provide equal resistance, even if possible, they can steal points from that match. Dani Olmo still seems far from Barcelona's reach and therefore it is difficult to convince the player to join at this time.
Hansi Flick, the new coach of Barcelona, even if he is able to bring in good results, I believe it is going to take him quite a lot of time. He is definitely not going to bring incredible results instantly. Barcelona definitely made a mistake by changing the coach. Because now they will have to give him a good amount of money to bring in the players that he wants as well. And for a club which does not have enough money to spend, that is an additional problem that I think they could have easily avoided.
But You know Hansi Flick has managed Bayern Munich and the German team before. So I guess he is probably going to be good enough to at least maintain the performance that Barcelona was doing.