The problem, I think, is that most other countries with extremely strict gun control took action right away, so that has been their "new normal" for years now. So, in their view, gun confiscation would seem like a no-brainer.

On the other hand, gun ownership has been baked-in for so long within the United States that the genie is already out of the bottle. I suspect the most effective solution would be a federal version of the middle ground that you touch upon.

Maybe write a more comprehensive article in the future on the pros and cons of various centrist gun control measures (and what their implementation might look like, in terms of practicality)?