Oh yes, Ethereum is a terribly expensive compute resource. I did a calculation a few months ago, comparing the hash power of the Ethereum network compared to an AWS EC2 instance. For 1 ETH, you can hash the Ethereum header ~320,000 times. That same amount of hashing can be done on t2.micro instance in roughly 5 seconds (sometimes less).
So, hashing on Ethereum is over 2 million percent more expensive than normal compute resources. However, you normally wouldn't do those sorts of operations on the Ethereum network, nor need that much compute power.
It all starts with finding a good blockchain development team. Good developers are tough to find and easy to lose if you did not satisfy the requirements. On the competitive market like blockchain development, great enginners are aware of how awesome they are (and rightfully so), so the bar is raised pretty high.
to keep a blockchain system running also comes at high cost. You need to buy a specific type of hardware, adapted to handle blockchain developemnt and maintainance, and invest a lot in servers as well. Read more in this article blockchain.intellectsoft.net/blog/cryptocurrency-development-and-types-of-cryptocurrencies/