When I try going to txdmv.gov, I don’t get the same server, but I do go to a machine that http-redirects my browser to www.txdmv.gov.

$ wget http://txdmv.gov/
--2024-04-10 17:01:26--  http://txdmv.gov/
Resolving txdmv.gov (txdmv.gov)... 168.44.227.138
Connecting to txdmv.gov (txdmv.gov)|168.44.227.138|:80... connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: https://www.txdmv.gov [following]
--2024-04-10 17:01:26--  https://www.txdmv.gov/
Resolving www.txdmv.gov (www.txdmv.gov)... 3.222.136.66, 18.234.22.91
Connecting to www.txdmv.gov (www.txdmv.gov)|3.222.136.66|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [text/html]
Saving to: ‘index.html’

index.html              [  <=>              ] 203.91K   986KB/s    in 0.2s    

2024-04-10 17:01:27 (986 KB/s) - ‘index.html’ saved [208802]
$

EDIT: Ah, apparently it redirects http://txdmv.gov/, but not https://txdmv.gov/.

considers

Based on @malloc@lemmy.world’s comment, maybe some browsers interpret a bare hostname without protocol specifier as an http address, and some as an https address.