Assuming this wasn’t sarcasm: For many hobbies the parts come from all over the world. You can’t expect hobbyists in every country to set up manufacturing for every part.

Even if they did, the raw materials have to come from other countries. The machines probably come from other countries. Setting up little factories all over the world isn’t efficient so prices would be extremely high. Parts might be cheaper importing from other countries even with extreme tariffs.

It’s all just a mess of bad policy. We lose out when governments restrict our ability to make small, simple purchases from other countries without heavy cost overhead.