In reply to Terence.

I don't see performance as big issue today. Quality server/hosting is cheap, caching solutions exist, image optimization too, HTTPS/2, PHP7 is coming ... it was never so easy that any website, even CMS with database can almost fly.
Regarding Jetpack ... I am not fan of it, anyway I can understand why people use it ... the same why so many users use bloated themes like Avada ... Both tools are not the best solutions, but what is important, they are solutions, not just plugin, snippet, line of code. People/businesses need solutions, not plugins and themes. So sometimes even clunky solution is better than just "the best" plugin or theme.