Technically already possible... (I used this, it works, and I liked it, but bottom line I did switch back to Windows 11 Standard bar)
Winaero Tweaker has an option under its Windows 11 section for 'Classic Taskbar' to turn on the old Windows 10 style Taskbar...
Once that is enabled, you can then change taskbar location to the side...
Several things will be broken, there will be a few links on the 'Classic Taskbar' to fix about 80% of the problems...
The 'Win-x' menu was still broken by doing this, and most of the icons Microsoft puts in the system tray were broken in some way (Wifi Connect menu was blank for instance)
But bottom line worst problem is that it is currently known for sure that Microsoft will continue to invest into the current Windows 11 taskbar, but it is currently unknown if the classic taskbar will get fixed or get worse over time... Will it get a Windows 11.1 that fixes the taskbar screw-ups like Win8 did? who knows...
I figured since I was going to have to help other people with Windows 11 on occasion I might as well figure it out and went back, though it is severely missed...