Currently (it's been years by now!) the only way to erase while using the brush is to hold the ~ ("tilde" in english) key. If you don't have a keyboard layout that supports that symbol, you are f'd.
I know posting in these forums is useless for trying to push for changes in any adobe product, but it would be quite nice if Adobe considers the huge user base that doesn't uses an enlgish layout by simply puting this feature available for customization in the keyboard shortcuts section.
Windows 10 x64
Gigabyte Aero 15 Photoshop 24.0.1
The only solution I can think of right now as a really cancerous workaround is (at least on windows) customize whatever keyboard layout you are using for it to have somewhere the ~ key as the main symbol. I'll have to resort to that for now.