Charles soon made a requirement: they could only bring things that could fit into a backpack.
The backpack became the standard. After the announcement, Charles posted a follow-up article.
If anybody exceeded that standard, they wouldn't be allowed to bring anything and would have to walk into the portal empty-handed.
Most people stopped discussing it when the rule was announced. They were all smart and knew it was time to behave. If they followed the rule, they could bring a few things with them. But if they didn't, they wouldn't be able to bring anything.
Most people knew what to do when they weighed their choices. But there were always exceptions.
A small fraction of people didn't think much of the rule. They packed things that could fill at least one suitcase. One of them filled an entire cargo and was going to drive it through the portal.