Should I use a page-builder app or native Shopify sections?

For most stores, native sections (Online Store 2.0) are the better default: they're built into the theme, add no extra app scripts, and are fast. Shopify's section/block system now covers most landing-page needs without a builder.

Page-builder apps are genuinely convenient for non-technical teams shipping lots of custom landing pages quickly, but they inject their own CSS/JS and can drag down speed if overused, and you're locked in (remove the app and the pages break). If you go that route, use it sparingly and keep an eye on Core Web Vitals.