Is it possible to deactivate the "New Learning Experience" per Default?
I assume that you are talking about the on premise installation. Please check the Instant Producer Installation Guide on the Help Portal. You can pre-parametrize your Instant Producer before the roll-out and set a parameter for the installation folder to be the user folder.
If you are talking about the cloud installation, you can define the download path for cloud installations in the Manager via Administration > Server Settings > Download Path for Cloud Installation.