I went to Seoul in late October and they had a price increase right before I went. I don’t think they’ve have an increase since then. What I bought, the sweet alhambra bracelet in carnelian, the savings was about $150 at the time. I guess it depends on the item, and what you feel is “worth it” but for small items like this, now thinking about it, I don’t feel it’s worth it to buy there vs the US. If it was a bigger item, I might feel differently.
Before I went, I also created a spreadsheet comparing the prices (US+tax) vs (KRW w/ VAT refund). You can check out the Korean prices on the site in English and all prices include tax already. The VAT refund rate is about 7.27%
Hope this helps!