So I don't think Lens will set too big a target next season in the Champions League because they are aware that the strength they have is not too strong to compete with other clubs who have great players and mentality in the Champions League.
Your conclusion makes sense, but nevertheless every team will try to do their best because there is a prize at stake every game they play. Lens also have good form as a competitor, but of course they don't look like the best contenders in the Champions League because other top teams tend to have strong chances and mentality.
In addition, Lens do not have much experience in the Champions League which means they will return home early after the group stage. But anything can happen, maybe next season will be different even though Lens' chances are very low.