Polly's apartment is smaller than Gabs isn't it? Or at least it seems like it, and she does international orders if I'm not mistaken? She's gave multiple different excuses and if she did ever open international shipping back up, she'd probably have lost most of that customer base. Why not just say "I'm just doing UK only for now, if that ever changes it'll be posted on IG/Website/etc."
Orrr...an idea, she could offer printable pdf files for those who lived internationally that wanted prints.
Added: I know Polly has an actual studio outside her home now, but prior.