In previous roles I’ve used BuiltWith before and it’s an invaluable tool. There’s a few companies with similar approaches except focusing on social media profiles (HypeAuditor comes to mind) that spawned in (iirc) 2017 after Instagram made significant changes to what data were available through their API.
It seems similar that Etherscan had this type of first mover advantage with automated data indexing and basic discovery tools for the Ethereum blockchain.
I wonder what the next wave of straightforward software utilities will be like.