The classic Ctrl + Z command steps backward through multiple history states by default, matching the behavior of other Creative Cloud applications.
Your (e.g., laptop, desktop, drawing tablet)? Adobe Photoshop CC 2019 20.0.4.26077 X86 X64 Portable
The portable version of Adobe Photoshop CC 2019 20.0.4.26077 offers several advantages: The classic Ctrl + Z command steps backward