PSG wants to focus on the Champions League and try to get the title in this tournament but they are not alone. Teams like Real Madrid also want the same thing but it was also hard for PSG to have any achievement in this tournament. Now PSG's first priority is the Champions League because they know winning the French League 1 is not hard for them considering the money they have spent on this team.
Currently, the only team they have raced with PSG is Marseille because of the good performance we saw from them but even Marseille is not strong enough to make any problem for them yet.
I mean when you win the league so many times in a row, there isn't really any feeling left in winning the league, so UCL is the only place to care about. When you win this many times, the league becomes so boring that even if you end up winning it, fans are not on the streets celebrating anymore, same problem is not rising for Manchester City as well, when they first became good there were some celebrations, but nowadays you do not see that many people end up caring when they win.
So for PSG, league doesn't mean anything, cup doesn't mean much neither, only thing that matters would be UCL, and if they win that then fans will go mad, that would be crazy and they will of course be super happy. Still, if they finish the season with two cups, league and domestic cup, and then start with their domestic super cup, then that would not be bad at all, that's still quite good. They don't do that very often, even though they win the league all the time.