That’s right, the percentage of users of Ruby on GitHub declined significantly over the last few years and it has dropped from the 2nd most popular language in 2017 to the 11th most popular language now.
However, it’s also important that GitHub is growing fast and the total number of users on GitHub has exploded in the last years. This means that even languages with a declining market share can still have a growing user base. Looking at it this way, Ruby has more than 3x the number of active users using the language than in 2011. Just it hasn’t grown as fast as other languages.
There are some other things to consider. GitHub was started by active members of the Ruby community, and much of their code is written in Ruby. This caused them to attract a large number of Ruby programmers in their early days causing Ruby to be overrepresented then. As GitHub grew its user base it naturally reached out to programmers in other languages. As more programmers who use other languages started to use GitHub, their percentage of users on GitHub increased. But they were using those languages before they actually joined GitHub, and so the real popularity of these languages was initially understated.
Statistics is a tricky thing and it looks like that even though the market share of Ruby is declining, the number of its users is still growing which is a good sign for a language with such a long history as Ruby. Who knows, may be one day, it will return to the top again.