While i'm not going to say one way or the other, I would point out that there are a few differences here.
1) Cryptopia's wallets have millions of transactions in SIGT in its history. That could be a contributing factor (in fact, they mentioned that in their post).
2) Cryptopia probably has significantly more wallet addresses than YoBit, despite them having more volume RIGHT NOW.
3) More volume does not mean more transactions. They could just be more value per transaction.
As such, I don't think you can compare an exchange that has only been trading in the coin for a short time, with one that's been doing so since the beginning. Even if said new exchange does more volume. It's an irrational argument.
Regardless, maybe the problem is with Cryptopia.. I just don't think it's useful to do such an unbalanced comparison.
Sigt using leveldb to manage data. Like most other coins. So there is no coin problem, it's just volume & leveldb engine problem. A lot of people mined and sold their coins on cryptopia cuz "What to mine" main page says this. Mining pools creates bunch of small payments. So any other coins with good volume and popularity like signatum can be delisted by cryptopia, just because they can't scale theirs wallets.
Just read this
https://en.wikipedia.org/wiki/Shard_(database_architecture)If the problem in amount of transactions\user wallets they can be splitted to 2\3\4\5 databases. Technically this is very simple. but for cryptopia it's easily to delist something than solve their technical problems.