The Liverpool and Arsenal match may not really be a serious one per say because both teams are not fighting for anything anymore as they already know how the season will end for them. But they might just play to keep records which is a good reason to see some form of interesting match. I will rely on goals and not who will win because both sides will likely score in that match. Arsenal may not be in the right frame of mind to defeat Liverpool after their Champions League loss to PSG and Liverpool too are not too motivated to play like before so they can settle for a score draw.
Have you checked the table Arsenal are still in a spot where they can lose the top four spot which would be very ironic fir them.
Also Liverpool are not really the kind of team that would often settle for a draw rather they are competitive and would want to win in order not for it to seems like they just dropped form after winning the EPL title this season. Two defeats in a row won't be actually funny to then.
I don't doubt that it's not possible but after missing out on qualify for the finals and potentially winning the Champions league, do you think Arsenal would still want to miss qualifying for top 4? I don't think so, even though they fail to finish as runners they usually finish, they would either finish in top 3 or 4, maybe your angle of judgement is cause they'll be playing against Liverpool next, but don't forget that Liverpool are already Champions and might not take the match very seriously since losing it doesn't count for them.
Those Liverpool players are currently taking a break most of them might even be spending more time with their families and less trainings since they've already won league and are not in any other competition. They'll even be avoiding having injuries that could affect them next season, so they won't be very serious like Arsenal who needs to maintain their position.