Legend style option has no effect in polaraxis

Question

Setting the global option label style in a polaraxis does not seem to have any effect. Is there a specific style to use in this case ? I could not find any in the documentation.

% arara: pdflatex
\documentclass[tikz]{standalone}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{times}
\usepackage{pgfplots}
\usepgfplotslibrary{polar}
\pgfplotsset{compat=newest}
\pgfplotsset{
label style={font=\huge},
}
\begin{document}
\begin{tikzpicture}
\begin{axis}[%
width=7cm,
height=7cm,
xmin=0,
xmax=20,
ymin=-2,
ymax=2,
xlabel={XXXXXXXXXX},
yticklabel style={rotate=90},
ylabel={YYYYYYYYYY},
]
%
\end{axis}
\end{tikzpicture}
\begin{tikzpicture}
\begin{polaraxis}[%
width=7cm,
height=7cm,
xmin=0,
xmax=360,
ymin=-2,
ymax=2,
xlabel={XXXXXXXXXX},
yticklabel style={rotate=90},
ylabel={YYYYYYYYYY},
]
%
\end{polaraxis}
\end{tikzpicture}

\end{document}

Example in axis

Example in polaraxis

Answer 1

From tikzlibrarypgfplots.polar.code.tex one learns that for polar axes the relevant key is polar labels style. There you can see that the x and y labels are treated differently for this kind of axis. (Footnotes 17 and 18 of the manual v1.16 suggest that these labels are tricky. ;-)

\documentclass[tikz]{standalone}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{times}
\usepackage{pgfplots}
\usepgfplotslibrary{polar}
%\pgfplotsset{compat=newest}
\pgfplotsset{compat=1.16}
\pgfplotsset{label style={font=\huge},polar labels style={font=\huge}}

\begin{document}
\begin{tikzpicture}
\begin{axis}[%
width=7cm,
height=7cm,
xmin=0,
xmax=20,
ymin=-2,
ymax=2,
xlabel={XXXXXXXXXX},
yticklabel style={rotate=90},
ylabel={YYYYYYYYYY},
]
%
\end{axis}
\end{tikzpicture}
\begin{tikzpicture}
\begin{polaraxis}[%
width=7cm,
height=7cm,
xmin=0,
xmax=360,
ymin=-2,
ymax=2,
xlabel={XXXXXXXXXX},
yticklabel style={rotate=90},
ylabel={YYYYYYYYYY},
]
%
\end{polaraxis}
\end{tikzpicture}

\end{document}