You are right but I think Juventus will try hard for both Serie A and Europa League because they know Europa League a very risky and even a team like Manchester United can lose everything in a few minutes while they were the first hope for the Europa League title I guess Juventus will have a hard day against Sevilla because they are very much unpredictable in Europa league.
The competition in Serie A is very hard and it is not easy to know what teams will be last three clubs in the top four at the final day. Even Lazio at the second position can be kicked out of top four after only two match days. Serie A has 6 match days left and with very narrow differences amongst competitive clubs, many changes can appear in coming weeks.
Juventus will also have tough matches with Sevilla in Europa League semi finals and no guarantee that they can beat Sevilla as well as win the final match. So they have to pay attention on Serie A in which they have good advantage to end it in top four. It is less risky than betting all in Europa League.
For Serie A, I think Juventus no longer have a big chance to win it this season. But for the European League, it is clear that it is still very possible for Juventus to try to win the championship this season, because Manchester United who have been eliminated from the Europa League this season is the result of the mistakes of their own players.
It is impossible for Lazio and Juventus to catch Napoli with current big gaps and only 7 matches left. I believe that they really mind about Scudetto which is unreachable with current conditions. They are aware of their difficulties in top four competition too and I am surely that they must wisely diversify their player resources for both Serie A and Europa League to have as best achievement as possible in this chaotic season.