It don't though, it just rises the price of energy because the gas still flows, even more than before, just from USA, Norway and yes, sill Russia, even more of it, but through middlemen. The sabotage also caused significant ecological catastrophe in the Baltic.

About the sabotage itself you have three versions available:

1. Truth, that USA bombed it, possibly with participation of Norway (note above paragraph, curiously the very same countries that gained the most on it, qui bono, eh?)
2. USA version, where Ukraine did it, despite lacking means
3. Official German/EU version, that is no version, because both above versions means that Germany is either vassal (ver1) or war ally (ver2) of country which attacked Germany in a biggest peacetime sabotage in German history.