There are a lot of limits on government powers! You can find them in the Constitution and the last 200 years of case law, and of course you're free to challenge

There are a lot of limits on government powers! You can find them in the Constitution and the last 200 years of case law, and of course you're free to challenge any of those powers even today. "The government has the ability to seize most anything" == there are not classes of items the government cannot seize. Rather there are circumstances under which they can and circumstances under which they cannot. I suspect the reason you're not seeing much adjudication about these circumstances (medical supplies during a pandemic) is that it's not that controversial an application in legal circles. Ah yes the vague "that thing I remember that I cannot point to."