I really think tldr-esque snippets should be mandatory in manpages. Manpages are important documentation for when you already know how to use a program, but sometimes (always) I don't have 30 minutes to read the entire manual to figure out how to start using a program. The ffmpeg man is practically a book! Meanwhile tldr can give me exactly what I need to get started. If there's no tldr and I can't grep something out of the man, then I'm using a search engine.
Not all programs have a --help, and --help doesn't always give you clear examples of how to use something. For example, ffmpeg's help gives a dump of all the options, and no examples of how you probably want to put them together.