[Doc]: Most of the pyplot examples don't use the pyplot interface

[StefRe]

Documentation Link

https://matplotlib.org/devdocs/gallery/pyplots/index.html

Problem

There are 19 pyplot examples but only 7 of them actually use the pyplot interface:

• Infinite lines
• plot() format string (very trivial)
• Pyplot Mathtext
• Pyplot Simple (very simple indeed)
• Pyplot Text
• Pyplot Three
• Pyplot Two Subplots

The majority of the "pyplot" examples in fact use the OO interface.

Suggested improvement

a) move the 12 example using the OO interface to the corresponding sections

or

b) rewrite them using the pyplot interface

While this doesn't appear to be a big issue to experienced matplotlib users it might confuse new users.

[jklymak]

They should be moved/removed and this section removed.

[story645]

Um I think this a dupe of #15922