Phenomenal job! Super methodical, and proof that UX/design is science, not just art, as many people mistakenly think.
However, like someone else noted in the comments, this exercise primarily takes into account the user’s perspective, and not necessarily the business perspective. It is notorious that at any given point in time, Booking runs thousands of A/B tests on their site. Many of them are tiny changes of UI components or copy amendments. I am positive that someone at Booking has tested removing some of the “noisy” blocks in the landing page, and measured the effect on conversion. If the blocks are still there, I want to assume that they had a negative business outcome and it was decided to keep them there.
All of this is dangerous territory for a titan like Booking. Any small UI change (not to mention a major redesign) is a risk that needs proper assessment and thoughtful execution.
Meanwhile, Airbnb and HotelTonight will continue eating more and more of their lunch ;-)