An em-dash is just Alt-(regular-dash) on most well-configured compose key configurations, it's not any harder.
This is also the default macOS/iPadOS configuration. (So I use em-dashes when I'm writing an macOS/iPadOS, but not on Windows.)
This is also the default macOS/iPadOS configuration. (So I use em-dashes when I'm writing an macOS/iPadOS, but not on Windows.)