Not one or the other of these ventures have a substantial use-case.
Im not sure about shiba. it's a defi token right now. Shiba itself already announced that on its official twitter. Shiba has shiba swap and it will be launched shiba blockchain as soon as possible. This may change the image of shiba inu to be a meme token. You can even check it directly. it seems like the vision of shiba inu is much stronger than doge coin. The doge coin must have needed a developer that can at least give it second layer blockchain to make doge coin can be integrated with defi and NFT.
In my opinion, Shiba Inu started like a meme coin and it is still such, however, it develops as its popularity grows. The project focuses on the most recognizable innovations. Of course, all this is part of the hype, but it gives the result. Developers are trying to reach new levels. Perhaps, initially, they also perceived this as a joke, but now, when they have achieved such discussion and recognition, they themselves have to take the project more seriously, thereby creating a more weighty ground under it.