Yes, it is actually very interesting. Barcelona has won more Spanish championships than Real in recent years, but Real is much more successful than Barcelona in the Champions League. In the last 2 years, Barcelona did not even manage to make it to the knockout phase of the Champions League. I really don't know how to explain it rationally.
Barcelona has had major financial and organizational problems in recent years, and the loss of Messi was irreplaceable.
Honestly, I don't see Barcelona as one of the favorites in the next season of the Champions League, unlike Real.
Manchester City remains the main favorite for the next season of the Champions League.
There is something really odd about Barcelona indeed. This tiki-taka system was working pretty well in the past and it brought even the Champions League title to them. Those times were Messi's prime time also of course. But some time later something started to go really wrong about this team. Even with Messi's huge contribution the team were still a failure in the end.
Messi's departure made things even worse about their CL performance. Therefore I just think that the same system doesn't work anymore. But Xavi doesn't seem eager to make substantial changes in his strategies. However if they fail in the CL in a similar way this season also then I would start to worry about Xavi's future in this team.

Because I don't think only winning the La Liga title is enough to satisfy the board.
I honestly think that the board cannot ask for too much from Xavi. Especially when he has actually brought stability to the team despite all of the problems that they had been facing. Barcelona should actually be happy that they are at least being able to win the La Liga title. Because the problem that they hadn’t been facing before Xavi came to the club as manager I don’t think that was going to be fixed by any other coach so fast.
Of course, if they could date someone like Zidane, they could probably get a little better result. But they did not have the money to bring in a coach like that. And no one actually wanted to take up the job because it was basically suicide.