I think it depends on how broadly the template is defined. If you can reasonably limit it to the portion of the UI that is impacted by the data then it isn't so

I think it depends on how broadly the template is defined. If you can reasonably limit it to the portion of the UI that is impacted by the data then it isn't so bad to have logic in the template. If the model is built on the server-side, this approach ensures you don't have markup polluting your server-side code and making it less manageable in the long term.