On the Delicious Brains site they have a new post that makes a suggestion to the WordPress plugin developers out there: stop supporting legacy versions of your plugins and move on.
I recently saw this tweet from Danny van Kooten which reminded me of one of the many major gripes developers have with WordPress – supporting ancient PHP versions:"STOP SUPPORTING PHP 5.2 IN YOUR NEW PROJECTS. No one using it is actively installing plugins, trust me."
Yes, (unbelievably) WordPress still supports installations of PHP 5.2.4! As plugin developers, we can’t change that over night but we have the power to stop supporting these legacy versions in our plugins where we have control over the codebase.
He talks about how, despite the fact that the WordPress project itself strives for ultimate backwards compatibility, it's just not run on older versions of PHP as much. They share some statistics about the number of WordPress installs on each version of PHP starting with v5.2. The results show that the overwhelming majority are on v5.6 with a split between <=5.3 and >=7.0 for the remainder. They also share some statistics from their own plugins finding that the >=7.0 takes the lead.
The post then shares some of the reasons for making the upgrade to only support newer versions of the language including security updates, speed and developer experience. It finishes up with some of the steps to follow to inform users of the intent to deprecate old support and when to make the move.