Horrid. Greeting card design follows trends as much as clothing does. There are types that go in & out of favour, illustration styles, colour schemes of the year. I don't especially collect cards, but I did have two. The third I received from my pal in England, Charlotte (@queenchoo) a fellow kitsch lady.
She sent me the fabulous silver foiled flamingo number. Very tropical! The Valentine's card isn't strictly vintage, it uses genuine antique images, but has been put together by a crafter & I bought it from eBay for my husband last Valentine's. The last card arrived through my letter box when we lived in our last rental house, from some long-lost-relatives of previous tenants. With no forwarding address I decided I'd put it up that Christmas anyway & have kept it's foil loveliness in the cabinet since.