I also agree more if Tuchel wants to stay at Bayern Munich rather than leaving there for Barcelona, because Barcelona doesn't just need a great coach like Tuchel. But it also requires several great players in several lines to be able to improve its performance to be even better, because currently Barcelona's decline is increasingly visible. Meanwhile, Bayern Munich is still quite good with its performance this season and is even still a candidate for the Bundesliga title.
Recently, Thomas Tuchel has been heavily linked with several teams apart from Barcelona he is also linked with Manchester United, what is even more surprising is that Thomas Tuchel has not ruled out the possibility of leaving Bayern Munchen. If you ask why Thomas Tuchel is interested in moving, I think the reason is because he hasn't been able to overtake Leverkusen at the top of the standings, surprisingly Leverkusen is still strong in the standings with an unbeaten record well, in a situation like this maybe Thomas Tuchel feels pressured and has failed so moving to another club is the solution.
But I also have other opinions, for example if Munich manages to win one of the Bundesliga titles or the Champions League, maybe Thomas Tuchel will take another option, meaning he is still worth keeping to handle Bayern Munich. We'll see what the situation is like at the end of the season because several options are still available.