Building products in web3 is hard because most products don't find any kind of product market fit. This has been the story for most ideas on the internet. The lack of product market fit has been lamented by a lot of frontier technologies over the past decade.
However even if you do find product market fit in web3, converting that into paying users is nearly impossible. Users will always use features which are free, however paying for a web3 service is the real test.
Most of the spending and volume one sees in web3 products is done by the users in the hope of a future reward in the form of an airdrop. These are not consumers, they are farmers and speculators and these signals mean nothing.
Last year I built a product called Appnd. It allowed content creators and users to attach content to their NFTs and in-game items. I showcased it to a bunch of people. Most said they would use something like this but not pay for it. It was a clear definition of product fit for a gap in the market but not of pricing fit because no one wanted it.