> You can make it narrow enough to only just fit the date at the bottom, without third-party utilities, which seems small enough.
Not sure about your system but on both of mine by default it's over double the thickness of the horizontal taskbar when small icons are used.
> Also also, if you do the maths, the typical vertical taskbar can be significantly thicker and use no more screen area.
So I measured this on my system with a 2560x1440px monitor (16:9 being a typical aspect ratio). Horizontal taskbar total pixels: 76800. Vertical taskbar total pixels: 96480. Vertical orientation still objectively consumes more screen real estate, unless the 7+ Taskbar Tweaker mod is used.
A sibling comment mentions a user with an ultrawide though, which due to the sheer width I suppose is a scenario where the default vertical is smaller overall. Or perhaps if larger icons are used.
Also, there's typically plenty of spare width and not much spare height, due to modern aspect ratios, so it's a win, anyway.
Also also, if you do the maths, the typical vertical taskbar can be significantly thicker and use no more screen area.