Ever since Ethereum was created in 2015, the whole crypto/Blockchain space improved in many ways that were never imagined. The ICO trend of 2017, and the current "De-Fi"/NFTs hype are all attributed to Ethereum's ever-rising popularity in the mainstream world. If it wasn't because of Ethereum, we wouldn't had a plethora of smart contract platforms to choose from. The crypto/Blockchain space would've been focused solely on finance, instead of serving as a hub for decentralized applications.
It's been 6 years since ETH came into inception, and now the smart contract platform is the second-largest blockchain network in the world. Some people compare ETH to BTC because of its focus on decentralization unlike any other cryptocurrency on the market today. As of this date, Ethereum has a large number of miners and nodes keeping the blockchain alive and healthy. If ETH continues to grow, it could live alongside Bitcoin for many years. But we all know that nothing lasts forever.
What's your opinion on this? Will Ethereum last forever? Or will it eventually die? Do you think it'll retain its place as the second-largest cryptocurrency by market cap for long? If not, why? Do competitors stand a chance against ETH? Your input will be greatly appreciated. Thank you.

There is nothing that last forever, every thing nor every one will disappear one day. Etherium is one of what a man develops and eventually gonna die in the future, for now we all have use it in different ways, earning it, making profits from it, develops another contract through to it but it does not mean it will lasts forever.