Can I suggest to replace the dated tutorial Adding plug-in parameters by the more recent Tutorial: AudioProcessorValueTreeState. I don’t think the new users, that start with the tutorials benefit much from writing stuff by hand, especially, since the SliderAttachment and the advice in the first tutorial, changing range and skew manually on the slider, doesn’t mix well.
Also the second example could reflect the new AudioParameterFloat constructor, so you set the NormalisableRange there with all the settings, that end up automatically in the Sliders.
Just a suggestion…