Earlier quoted context omitted.
That’s not what the stats show. WordPress powers 43% of websites today. Shopify, Wix, and Squarespace together only account for 11%. https://w3techs.com/technologies/overview/content_management
Here's their "10 popular sites using Wordpress" - microsoft.com - It's not wordpress, probably home grown - wordpress.org - This one's a freebie - digicert.com - Using Adobe Experience Manager, per script includes - wordpress.com - Another freebie - mozilla.org - No, using a homegrown CMS: https://github.com/mozilla/nucleus - nih.gov - It's using Drupal, per a meta generator tag - forbes.com - No real for or against…
* microsoft.com – uses WP at devblogs.microsoft.com
* digicert.com – may be a false positive, they link to files at /wp-content/ URLs, maybe they used WP in the past and kept the URLs?
* mozilla.org – uses WP at blog.mozilla.org
* nih.gov – uses WP at directorsblog.nih.gov
* forbes.com – can’t tell, my ad blocker breaks their cookie consent screen
* archive.org – uses WP at blog.archive.org
* nginx.org – uses WP at blog.nginx.org
* ebay.com – may be false positive?
We end up with 2/10 potential false positives, and one unknown (and even then, those are huge sites, who knows if they’ve got WP hiding under some deeply-buried subdomain).
I agree with you that Microsoft and TechCrunch probably aren’t FTPing their files in, but even if we assume that only 50% of WordPress sites are doing so, that’s still more websites than the next 10 competitors, combined!
If you think about it, this makes sense: do you reckon your local small businesses have a TechCrunch-level web presence, or are they using GoDaddy? Now consider that there exist many more local businesses than TechCrunches.