In terms of technology, ETH is at the top because most Altcoin is running on ETH. However, it should be noted that some Altcoin platforms such as Wave, NEO ...
But sometimes Ethereum always gives things that can't be expected, such as a failed network and always a nuisance.
Then MyEtherWallet is always hit by hackers with the Pishing website.
It's very unfortunate for that but I fully support Ethereum.