Depends. If it's a threesome, I don't want a girl with long nails, as it means she's not into other girls. Otherwise, don't care too much as long as she's careful.
People never surprise me with weird shit they assume about groups they don't belong to.
1. If I need to finger a girl I can put on gloves with cotton balls in the tips
2. Not every girl wants to be fingered, many don't like it
3. Unless you belong to a group, avoid making weird absolute statements about them.
4. I'd fuck your wife, please don't play with me and my long nail having bi ass self (not as long as these examples, but still like, an inch long)