I don't think Chelsea will be strong enough to contend for the league title and compete with the other top teams, Pochettino will start a process of rebuilding the team to become formidable thus I don't think the squad will be strong next season, meanwhile Arsenal having known their weak areas and points in their squad last season had strengthened their midfield and signed a new defender Timber obviously the team is now solid and will continue from they where they stopped last season, Man City, Liverpool, Man Utd and Tottenham are other clubs that had strengthened their squad too thus makes next season to be one of the toughest season and I am very sure other mid table clubs will also up their game as well.
Your opinion can be right can also be wrong I know you say it because you haven't seen Chelsea moving in this transfer window but this is not final, the transfer window is still available more than 3 weeks this means that Chelsea still have time to do something including negotiations so we have to watch first. Based on quality actually Chelsea players are not bad we believe they just haven't found a suitable coach and now Chelsea have Mauricio Pochettino, hope is on him to bring change although the main target is not the title but Champions League zone is enough so that the time will answer.