Sure. HTTP/1.1 isn't the only network protocol, though, IETF standardization or otherwise.

For SMTP (which this subthread started with):

   In addition, the appearance of "bare" "CR" or "LF" characters in text
   (i.e., either without the other) has a long history of causing
   problems in mail implementations and applications that use the mail
   system as a tool.  SMTP client implementations MUST NOT transmit
   these characters except when they are intended as line terminators
   and then MUST, as indicated above, transmit them only as a <CRLF>
   sequence.

https://datatracker.ietf.org/doc/html/rfc5321#section-2.3.8