I think @michaelosthege recently “fixed” that in Pytensor.
This is not a bug though, it’s just a less desirable behavior. (None, None) is a valid supertype for any matrix.
The reason is that static shapes are quite recent and we are still updating Ops to reflect them when possible.
If you are interested, would be nice to get a list of Ops that still lack obvious static shape output and even start improving them. We can use all the help 
That should be done in our PyTensor GitHub repository.