Luit is right. Nothing changes for shipments with value over 22€.
This is the reason why I haven’t bought San Marino BU sets at UFN for years, because it’s simply too expensive. It is much cheaper for me to buy it from coin dealer (or even better, at eBay).
But I think this change will have a big impact on the delivery times of shipments. I can’t imagine how customs will process all shipments besides those from China.
At least in Slovenia, customs charges 10€ only if they have to open a shipment and check the contents. If they don’t need to open a shipment, they charge lower fee. Higher fee could have been avoided if the invoice had been inserted into the plastic bag outside of the shipment. Or even better. If Europe is adopting such directives, then they could also build a system where the seller would send the invoice and the shipment number electronically, which would certainly simplify the procedures and reduce cost for customers. At last, a large part of the new financial packages is supposed to be dedicated to digitalization...!?!
Unfortunately, reducing cost for customers is not the aim of this change, I think...

The main targets are, at least I think so, Chinese web shops. Coin collectors are only collateral damage.