This isn’t the whole reason, and likely only a small fraction of it. There are a whole lot of other OSes that don’t fit into these categories, or that simply refuse (on purpose) to share their OS type. That wouldn’t be Windows.
I edited to include the chart I’m talking about (here). It includes a section for Other as well. I’m not saying it’s the whole picture, but it’s the reason for that bump in Unknown which may be increasing the overall percentage depending on when that data in the OP was pulled.
This isn’t the whole reason, and likely only a small fraction of it. There are a whole lot of other OSes that don’t fit into these categories, or that simply refuse (on purpose) to share their OS type. That wouldn’t be Windows.
I edited to include the chart I’m talking about (here). It includes a section for Other as well. I’m not saying it’s the whole picture, but it’s the reason for that bump in Unknown which may be increasing the overall percentage depending on when that data in the OP was pulled.