Divi is installed on millions of WordPress sites. It is powerful, flexible, and well-documented. It is also responsible for some of the slowest, most bloated websites I have ever audited. The tool is not the problem, the way it gets used usually is.
Where Divi Works Well
Content-heavy sites where non-technical users need to edit layouts. Multi-page brochure sites where visual consistency matters more than performance. Marketing landing pages that get A/B tested regularly. Client sites where the client will be making ongoing content changes without developer support.
Where It Hurts You
Performance-critical sites. Divi adds significant render-blocking CSS and JavaScript. If Core Web Vitals matter for your SEO (and they do), a hand-coded site will consistently outperform a Divi build. E-commerce sites where page load time directly affects conversion rate.
The Middle Ground
Use Divi with a lightweight child theme. Dequeue scripts and styles you do not need. Use Divi's built-in performance settings. Host on a fast cPanel server with OPCache enabled. Done right, Divi can score 85+ on PageSpeed. Done wrong, it scores 35.