More worrying is that the article doesn’t mention scamming! These seem like “legit”" charges, added after the contract was agreed!
“However, customs charges are the responsibility of the customer, not the retailer, who often has no idea of how much the eventual extra cost might be. They cannot be paid in advance and are levied only when the item reaches the UK.”.
“The extra charges are usually collected by the courier on behalf of the government, with customers asked to pay before they can pick up their package.”
This is madness (but we Remainers predicted as much)!