The input_*. entities are not part of the current Home Assistant data model, cannot be linked to devices and do not seem to have evolved.
Perhaps the creation of a new helper integration called Inputs (or another name that makes more sense) where it is possible to create helper entities that in the long term will replace the input_*. entities with entities from the standard domain, for example input_text. → text., input_boolean. → switch., input_number. → number., etc.
With this, the helpers would have the same data model as the rest, would allow linking to devices and would maintain the same standard and behavior for users.
It may seem like a too drastic change, but the input_*. entities were conceived and built when Home Assistant had a completely different data structure. Currently, they are not compatible with all the features that have emerged.
The suggestion of creating a new integration and keeping the current input_*. unchanged I believe would facilitate a smoother transition, as in the future the old ones would be deprecated and removed.
The input_*. are nothing more than autonomous entities, it makes more sense that they were from the same domain and model as the Home Assistant entities.
In practice, they behave the same way, the only difference is that one (almost always) interacts with the real world and the other does not.
But for the end user, both look identical and behave the same way, they just have different names, which is confusing for a regular user.
Also, inputs_* do not follow the documented entity models and have limitations such as not being able to link them to a device because they do not have a configuration input. Even the configuration flow does not follow the standard.
There are arguments for changing from both the end user and the developer perspective.
But ok, it’s okay to ignore this and insist on the argument that they are different things.
This does not have to be something that anyone is right about, I just wanted to raise this point that I find incoherent.