Open Source is a way to create but is not limited to only software but many different things. LLMs are software. Most open source LLMs are using Open washing to label themselves as Open Source, however it is not. The importance in Open Source is being able to study how it was made and most of open models have closed training data-sets and training method. Apertus is trully open in the sense that they published Open Data and full training details.

You have the right to be bother by "AI" but let Open Source enthousiasts being... well, enthousiasts when in a field of Open Washing someone created something trully Open Source to the point of sharing it in an Open Source community on a FOSS plateform.

Edit : Minor corrections