It seems that everyone already knows which way Sevilla will finish and I think they will be at the bottom. There is no compelling reason other than that at the moment Sevilla is very fragile and will not be able to compete in the group. Most of their opponents are teams that have been very promising since last season and perhaps Sevilla's only advantage is winning the European league. Especially with the absence of goalkeeper Yassine Bounou, it will be easier for Sevilla to break into the goal.
Anyone can think that a team can fail straight away, but that can't be 100% true when a team that can start quickly fails to qualify like Sevilla.
The four teams in group B, including Sevilla, look strong in their own league. Arsenal is strong in the English Premier League, Lens is strong in Ligue 1 even though they only have 1 point from the 4 matches they have played. If we look at last season, Lens was PSG's toughest competitor in the race for the Ligue 1 title. PSV Eindhoven was also strong in the Eredivisie.
Group B is equally strong, including Sevilla as a team that will compete with 3 other teams. This season, in my opinion, Sevilla can qualify from the group stage.
Don't look at Sevilla from the loss of several important players like the loss of Yassine Bounou.