Those are about the typical odds I've seen as well. The first batch, one chick had to be helped to hatch as it seemed to have been shrink-wrapped, even though the humidity post-lockdown had not dipped below 60 and the incubator hadn't been opened. But only three of that batch survived, and we eventually opened the other eggs very carefully, and found that they were all clear, as if they had not been fertile (but I think they simply had not made it past the shipping saga).
Basically, I would say if you buy shipped eggs, expecting a 10% hatch rate, you should be less disappointed when this is what you actually get. Be prepared to pay for 10 eggs to get one or two chicks. If the price of those eggs is worth the low numbers of chicks that they will produce, go for it. If you would feel highly disappointed to get a 10-15% hatch rate, then find another way to acquire what you're wanting. Shipped eggs can sometimes be 100% DOA, and, on the other hand, it is possible that you might get as much as half to hatch, or more. Expecting more than 50% hatch rate on shipped eggs is a sure way to be disappointed, and even a 25% hatch rate may not be yours. Anything above 50% is a lucky fluke of the mail system and/or a credit to the seller who packed the order. But the dismal hatch rates are unlikely to be the fault of the seller in most cases.