So much about web performance is linked to what's in your <head> which this article (and very useful looking tool) breaks down well. deadhead.cevdet.ch/blog/what-10...
What 10,000 home pages put in their head · deadhead
Deadhead 0.2.1 on the Tranco top 10,000 home pages, as served and after scripts ran: what the most visited sites ship, with the data behind every number.
deadhead.cevdet.ch