Yes, it’s mainly about expectation. For an actual use case, I noticed this when mentioning an IRC channel name, which became a long, distracting and useless hashtag link, exacerbated by agglutination and multi-word hyphenation typical in Finnish, (e.g. #channelname-irc-kanavalla). I tried to make it less distracting by editing in a preceding backslash, only to discover that it didn’t work here.
There is no way to escape a word-starting hash character (#) in plaintext.
Steps to reproduce
In MM 7.3.0, post this, verbatim: \#anything
Observed behavior (that appears unintentional)
Workaround: instead of ”\#anything”, post this: #anything
Using backticks (`\#anything`) also works, but obviously the word then gets formatted as code and not plaintext.
This is mainly an issue of inconsistency and surprise: backslash works to escape most other special formatting, so I’d expect it to work here too.
Still present in Nextcloud 3.21.2. My device is a Samsung A9 running Android 10.