Even if they're still being traded elsewhere, I wouldn't suggest that risk. It's too much trouble getting into a coin that everyone else is abandoning. If the exchange is delisting multiple pairs, it's for a good reason. No one is buying it and it is becoming useless.

Too many shitcoins emerged last winter and we are starting to see the decline. They couldn't have all survived through such an aggressive market, so we can see they are getting weeded out one by one. Hopefully this is a form of evolution and more reliable coins can enter the market as a result.