I find vertical tabs to be more useful specifically when I have more tabs. Currently using vertical tabs on Vivaldi and I can see 28 and a half tabs without scrolling, which is pretty alright if you're asking me. And Workspaces are quite helpful for the same reason.

For anyone curious, I currently have 2 workspaces at 8 tabs, 1 at 20, 1 at 25 and one at 82, which comes up to 143 tabs , plus 1 more tab in the default Workspace Vivaldi creates, coming up to 144 tabs.