Why can't tabs just be a visualization of browser history with the most recently used entries cached and bookmarks can go to hell (aka just be used for a hotbar)
For me not really. Open tabs are a TODO list, that are organized by work session. They get opened next to each other while I am working, and when I come back to that work, I find the tab group. I clean them up when I no longer need certain pages, and only leave open the ones with unfinished business. I visit literally hundreds of pages that are closed per open tab.
It is like I have a huge desk with papers that appear to be strewn across it, but actually are organized and the layout is important to my train of thought.
I can't understand the tab thing when history is pretty easily accessed in modern browsers... but it's common enough not to judge too harshly.