Lazy-load ads vs load-everything

Lazy-load ads vs load-everything
Load-all-units-upfront wrecks your Core Web Vitals and the below-fold ones barely get seen anyway.
Lazy-load below-fold slots (fire ~200px before they scroll into view) → page feels instant, viewability on those units actually goes UP because they load right when eyes arrive.
Don't lazy-load the above-fold unit though — that delays your highest earner for no reason.
Rule: eager-load slot #1, lazy-load #2 onward. Best of both.
Test it on one page first.