There's 2 very different issues there. On the EU goods being more expensive, sure. That's down to both regulatory standards and some protectionism. The EU certainly doesn't want China dumping vast quantities of below cost textiles into the EU market (which happened recently due to UK incompetence or fraud) and damaging European textiles companies. When we leave the EU we can certainly buy in some stuff cheaper. On the regulatory side though, our choice then becomes do we want to start buying in lower quality products which could well have been produced under substandard conditions and which don't carry the quality guarantees we've come to expect? Is that a price worth paying?
As for just replacing things made in the EU with things made locally, the question then becomes what was stopping us before? Either we can't do it as cheaply or we can't do it at all. If we can't do it as cheaply now then what's going to make it cheaper once we leave the EU and don't have tariff free imports on materials and parts? Again the only option is to reduce regulations and settle for substandard goods. So maybe we go back to kids toys made with lead based paints or cows fed on mashed up bits of other cows. Yay..
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