I see fine with glasses on, and I don't *need* 200% zoom because of vision-reasons as long as I wear my glasses.
However, even when wearing glasses, I often end up browsing the web zoomed in, because of unrelated *cognitive* reasons, or because it's a preference (eg. sitting far away from my screen).
But keeping them on all day isn't always possible, and the moment I take them off I can't read text, icons, or outlined items anymore, and I *need* zoom to work or I can't use the page.