I would hesitate to judge based on what's "easy to type" on the keyboard in front of me.

A lot of editing tools and processes automatically converting `--` to `—`, so folks editing markdown or using a Word processor might get the emdash automatically. Similar things are often done for matching double quotes. I wouldn't be surprised if quite a few WYSIWYG CMS systems do this conversion too.

There are also a lot of input methods that make it trivial to write special characters.

Apple famously uses the Alt/Option key to make inputting a lot of special characters simple. Look at any place that does a lot of writing and publishing, and you're bound to see a lot of Macs.

On Windows, you can memorize and input code points pretty easily as well if you have a number pad. Just hold Alt and punch in the 4-digit character code.

I hop platforms a lot, so I commonly use digraphs with Ctrl+K in VIM, or TeX input in Emacs to insert unicode characters. I'll also use `Ctrl+x 8 <RET>` to insert characters by name in Emacs when I need to search for something specific.