Somewhere between all the convert things to OO and restructure gallery PRs, the pyplot section of the gallery now has very little pyplot content:

PyPlot

• plot() format string
• Pyplot mathtext
• Pyplot simple
• Pyplot text
• Pyplot three
• Pyplot two subplots

OO

• Align y-labels
• Annotate Transform
• Annotate a plot
• Annotate Polar
• Auto Subplots Adjust
• Boxplot Demo
• Dollar Ticks
• Fig Axes Customize Simple
• Simple Axes labels
• Adding lines to figures
• Text Commands
• Text Layout
• what's new examples in highlight examples of new features in gallery #15920

I think there should be a standalone pyplot only gallery page, but think for this PR a potential resolution would be to sort the OO examples into the correct sections (possibly combining them with existing content) or altogether remove them if they're not adding any information.

xref: #15355 because I think this contributes to some of the confusion discussed there.