I checked the latest tagged releases to make sure the problem was on my side, so I ended up runing (on the running server):
pip install geoviews==1.9.1 pip install holoviews==1.14.2 pip install param==1.10.0 pip install datashader==0.12.1
and I saw the bug was no longer there .. bu this also messed-up my jupyter widgets .. hence a rebuild
Now I want to check if mamba is doing the right things otherwise I will try pip.
opts.defaultsto set default for the whole notebook supposed to work for hvplot? If yes, I'll submit a new issue.
My guess is that opts.defaults would work only for options not processed as hvplot command-line arguments, except maybe for some that are just passed through. Basically, HoloViews's option system lets you use opts.defaults to set global defaults, but then those defaults get overridden by any values specified explicitly. Due to how hvPlot works, I would assume that it sets various options explicitly even when the user doesn't provide values, in part because hvPlot defaults need to match Pandas defaults, not HoloViews defaults. So no, I don't think hvPlot not being responsive to changes in opts.defaults counts as a bug.
I frequently find myself using
hv.Spikes to plot a Fourier Spectrum, e.g., a statement like
hv.Spikes((n,abs(y)-y_min), "index", "abs_y").opts(logy=True,ylim=(y_min,1.01*y_max), position=y_min)
I am wondering if it might be advantageous to include an interpolation method
hv.Curve that produces such a plot?