YouTube Ads vs TikTok Ads — which is actually better for top of funnel?

Running a test for a health supplement brand. Decent budget, top-of-funnel awareness goal, eventually want to retarget for conversion. YouTube: Using skippable in-stream. Getting views cheap but the audience quality for retargeting feels thin. People watch 5 seconds and bounce.TikTok: Better engagement but harder to retarget since the ecosystem is more closed. Anyone have a framework for which platform to use based on product type/audience? My gut says TikTok is better for younger demo (18-34) and YouTube scales better for 35+ especially with longer-form content. Also has anyone tried running the same creative on both and compared? Curious if video that works on TikTok dies on YouTube or if good creative is just good creative.

TikTok wins for 18-34 engagement, but for supplements, YouTube scales better for 35+; just don't copy-paste creatives, as TikTok style feels too organic for YouTube In-Stream placement.