With vertical tabs, you don't have this problem. Every tab is the same width, making them easier to interact with. You'll need to vertically scroll the list if it gets too large, but that's a natural enough action. In this situation, you now close tabs because you want to, not because the browser is strong-arming you into it.
Where things really get fun is with vertical tabs that track ancestry, like Tree Style Tabs or Firefox or what's built into Orion. These tabs will nest as you follow links from one page to another, capturing context.
HN is a perfect example of where this works well. I can go to the home page, see a few stories that look interesting, open each comment page as a child tab. Then on each child I can open the associated article. And, as I read the comments, I can open new links that look interesting and that page is now associated with the root story.
I could bookmark all of these pages, but short of creating folders for each story there's no good way to capture that context. Naturally, that makes it harder to restore the same state when opening bookmarks. Instead, I leave the tabs open and when I'm ready to take an action on them (read an article, make notes in Obsidian, bookmark into a topic of interest) I do so and then I close them out. It makes context switching much easier when I know I'm not going to lose the context I just left. As an added benefit, I find if I leave tabs open I get better use of the browser cache than I do if I close an open later from a bookmark.
https://addons.mozilla.org/en-US/firefox/addon/grasshopper-u...