Ah, There's a distinction here with model vs model framework. The ollama inference framework supports token output restriction. Gemma in AI Studio also does, as does Gemini, there's a toggle in the right hand panel, but that's because both those models are being served in the API where the functionality is present in the server.

The Gemma model by itself does not though, nor does any "raw" model, but many open libraries exist for you to plug into whatever local framework you decide to use.