Leverkusen did not suddenly become a solid team, they have developed their performance since Alonso took charge of Bayer Leverkusen. In the middle of the 2022/23 season, Alonso took charge of this team which was slumped in the relegation zone. Gradually, under his guidance Leverkusen was able to finish in sixth place in the Bundesliga. Last season, Alonso added strength to his team by bringing in several newcomers and in the end they were able to break the dominance of the giant Bayern Munich. The point is, thanks to Xabi Alonso's touch, Leverkusen was able to perform perfectly without losing. Although, in several matches there was luck involved.
Talking about Leverkusen's defeat in the second week of the Bundesliga, their opponents were not a weak team. Although Xabi Alonso's team dominated the course of the match, Marco Rose, Leipzig's coach, did not mean that he did not study the tactics and weaknesses of his opponent's team. This is football, not always a team will win all matches. IMO, the defeat to Leipzig last week actually made Alonso evaluate the weaknesses of his team more. with the defeat, he has work to do so that in the matches they will play they can show maximum performance and win the match. well, this defeat is something natural.
Leverkusen really turn monster under the leadership of Alonso last season by destroying any team they come across, Alonso had really helped Leverkusen to be popular, before I considered them worthless to compete for the title, I equally agreed with you that they are in the stage of collapsing before Alonso came and moved them from nothing to something, in last four seasons the end up in three place hoping they will improve to the top the following season but unfortunately the declined in their performance and drop down to sixth place, then Alonso appear and rescued them to the top of the table from the beginning of the season to the end as the champions of bundesliga title.
Following their defeat for the week two actually shocked me because even though I wasn't expected them to play like last season I don't expect sudden defeat, I was expecting them to face defeat maybe when playing with Bayern Munich or other tough team, I see this as avenue for Bayern Munich to take the lead but still the league is just starting.