It's not about security. As you said, it's because Flash is more popular, so killing it will disrupt more users' workflows. It's a pragmatic decision… Person

It's not about security. As you said, it's because Flash is more popular, so killing it will disrupt more users' workflows. It's a pragmatic decision… Personally, I'm hoping we see a WebAssembly build of Flash eventually (once WA is featureful enough to support it), at which point the native plugin can die without breaking (as many) old sites.