This is what I would expect, but it doesn’t do differently as I use only a wheel. Could it be somewhere in the settings of the KDE itself?

Unfortunately, Alt+Wheel doesn’t work. It does the same as Wheel only. This is how it was forever. I’m not in fit page or fit width mode, no. Never worked with older versions, nor with the latest plasma Fedora 40 KDE spin where Plasma 6. All my mice with a single wheel and do not tilt. I’m out of luck.