In my opinion, even though Erik Ten Hag wanted the Bayer Leverkusen key players that left the club in the summer transfer window to remaining at Bayer Leverkusen this season that wouldn't have happened because it seems it was the Idea of Bayer Leverkusen management to cash in on those players. With the attitude Bayer Leverkusen showed in the two matches they played this season, they might likely not make it to the top four.
Leverkusen are in a precarious situation at the start of the season, so it's a bit difficult for them to do well this season. I'm still not sure what they'll do now that Ten Hag has been sacked and whether they'll hire a new coach or not. The impact of such a precarious situation will definitely be felt on the pitch and I expect it to be negative.
Since Bayer Leverkusen management relieved Erik Ten Hag of his job as Bayer Leverkusen head coach, they are yet to hire a new coach as Erik Ten Hag's replacement. I believe Bayer Leverkusen will have no choice but to play with an interim coach for the time being. Bayer Leverkusen has put themselves in a difficult situation this season, and they will pay for it dearly by struggling to win their matches this season.
Yes, Leverkusen have become much weaker this season than they were last season and their performance has improved. Under the leadership of interim coach Ten Hag, they have performed poorly in almost every match they have played, since Leverkusen has not yet appointed a coach, so this season will be very bad for them. Maybe this season will be bad for the team because of the wrong decisions in Leverkusen's management and their performance is not good, which is why they are facing difficult situations, of course, they will understand its value from the season.