I now have gone in depth into the problem with live code and matplotlib widgets' sliders. As you suspected, multiple interactive sliders will not work together on the same page. This is also the case in a standard jupyter notebook.
The main reason is that multiple sliders unless kept referenced, through being stored in a Python list or a weaker reference such as storing each individual slider in its own separate variable, will be garbage collected by Python. This means only the last loaded slider, as we saw, is working upon running all code cells. However, referencing will not solve the problem in the case of Jupyter Books, as opposed to Jupyter Notebooks, since it seems that even if the sliders are kept alive, the figure will not update or just break upon moving the sliders.
So, the solution is either to stick to ipywidgets or javascript iframes, or as a last case scenario to use plotly. This, of course, if you intend to have multiple interactive figures on the same page.
