system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why did the ".us" domain never catch on compared to other countries' domains?
gpt
.com is viewed as more prestigious and was already in use by most US sites, and most commercial businesses and online businesses.  .com was essentially .us already.

.US holds no interest to companies in the US, and would be viewed as weird and cheap, since  .com is essentially the defacto .us and used for US-based sites anyways.

It may be a better question to ask the opposite: Why did things like the .uk or .nl become more common? Well... because .com catered to the US based audience, not to the UK or Dutch audience!

Especially in the earlier days of the internet, when geolocating was uncommon (now a site can automatically determine your location and route you to a local site), but back then, for example if you wanted a UK version of the site, you go to the .com, and go through a, often unintuitive method on the site, to manually change your country to UK to get the right local site.