Shopify is pretty good, but if you have a small independant shop the hard part is getting visitors. On that basis etsy is better, because it gets a lot of traffic, but I think facebook will be even more popular.

I'm a member of a couple of local groups, largely for buying/selling kids clothing/toys. Something like that wouldn't work so well on other platforms - getting cheap stuff locally.

Of course etsy has its own problems, with a large number of their shops just being fronts for aliexpress resellers.