I mean Dortmund could have even won here without showing a decent performance. Because I can't say that they were good at all today. But it is normal to see that because of Leverkusen's great system. Especially in away games your job is much more difficult against them.
I believe Dortmund would be disappointed with the way the game ended even though they didn't play well. They had an opportunity to win the game after they went 1-0 up. They kept missing their opportunities. Dortmund, despite not playing well were very good defensively. If they weren't that good defensively they would have lost.
Nothing can stop Leverkusen to win Bundesliga this year and I will keep this bold prediction for the rest of the season. Sure , Bayern looks strong , healthy and always ready to win but Leverkusen looks more like a team than Bayern in my opinion and this will be a huge advantage when they will face each other later.
Leverkusen play very good football. They are very condinated and it's obvious they're a very well coached team. I believe they'll fight to the end for the league, but I can't conclude that they'll win tge league. The season is still a long way to go and anything can happen. Injury is something that can ruin a teams season. A major player gets injured and the whole team might start struggling.
Fatigue is also another thing that can ruin a clubs seasons, so I feel it's too early to say Leverkusen would definitely win the league.