Hello,
No idea how bad it really is with the planes there, we were there 4 times at different times of day, it was very quiet.
Lindenthal is not directly in the flight path, but still quite close.
Leipzig is a cargo airport. The little passenger traffic during the day is just a fig leaf to grab subsidies. The highest "passenger numbers" were reached at the airport during the Iraq and Afghanistan wars. Many American soldiers changed planes in Leipzig on their way to deployment.
Most of the air traffic takes place at night. Specifically from 10 p.m. to about 5 a.m., if I still remember the flight schedules correctly. We were involved in planning the DHL Express hub.
The cargo planes are mostly somewhat older and therefore louder aircraft. DHL Express has several modern 777s in Leipzig, those are still okay, but the rest is more in the heavy metal category.
There are also two or three Antonov 124s stationed there, I think they are not exactly quiet either.
So rather imagine being on the property at night, that could be much more interesting.
Best regards,
Andreas