So what is the difference?

Context predictiveness. Isotope infers an intact electron shell. Nuclide infers insignificant interest in the electron shell.

__________________
For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

I had always used it as isotope refers to the nuclei which have a particular number of protons and a particular number of neutrons, though usually in the context of the number of arrangements with a fixed number of protons. A nuclide is the same arrangement, but doesn't carry the implication of variation within a specific element. There is no condition depending on whether we're talking about ionized species or not. This is purely about nuclei, not electrons.

Note that there is also a term isomer which refers to the specific possible spin states within a given isotope, but I don't know of a parallel term conected to the nuclide family of terms.

__________________
Forming opinions as we speak

Google's definition:
"A nuclide is any particular atomic nucleus with a specific atomic number Z and mass number A; it is equivalently an atomic nucleus with a specific number of protons and neutrons. Collectively, all the isotopes of all the elements form the set of nuclides. The distinction between the terms isotope and nuclide has somewhat blurred, and they are often used interchangeably. Isotope is best used when referring to several different nuclides of the same element; nuclide is more generic and is used when referencing only one nucleus or several nuclei of different elements. For example, it is more correct to say that an element such as fluorine consists of one stable nuclide rather than that it has one stable isotope."

__________________
-----> Be prepared to accept that everything we know is wrong. <-----