This is a unique feature of Kratos/Hydra, you can use your own frontend components. With many other implementations this is not possible.
What do you mean by "much more opinionated client", there is a set of standard flows that your app has to handle and thats it for most cases.
If you want out of the box components they also have a paid version for that (and code examples in OSS)
Comments
Hydra and Kratos do not come with any frontend components, it's essentially just an API you have to write a a much more opinionated client for.
This is a unique feature of Kratos/Hydra, you can use your own frontend components. With many other implementations this is not possible. What do you mean by "much more opinionated client", there is a set of standard flows that your app has to handle and thats it for most cases.
If you want out of the box components they also have a paid version for that (and code examples in OSS)
Kratos does have a reference UI implementation: https://github.com/ory/kratos-selfservice-ui-node