I recently came across several partners who had applied preload too aggressively in ways that were making every performance metric worse, and when asked why, they shared Lighthouse reports that told them to do so. I think there are a couple culprits in Lighthouse where the preload advice is too aggressive and we should scale back our preload recommendations.

Examples:

• Recommending to preload an optional font so that it's used is bad advice for mobile connections that won't end up using it anyway. Given how contentious this audit was in the first place, it seems clear to me that this is more of a case-by-case basis recommendation and shouldn't be a blanket recommendation on mobile. Proposed action: Mark this audit not applicable on mobile (I might even want an audit that says "DONT'T preload an optional font on mobile")
• Preload of swap fonts. A particular site was preloading five different webfonts because Lighthouse told them to which resulted is a massive ugly tradeoff in 2s LCP delay (due to contention with the render blocking stylesheet) in exchange for like .01 CLS improvement. Proposed action: don't suggest preloading fonts with a non-block font display when throttling method is simulate (in applied throttling Chrome will have already rendered), tbd language changes that the preload audit isn't meant to be followed blindly, it's a "pick the important 1 or 2" situation
• Maybe more...