TL;DR: Can hastags be hidden? Yes with a "but".
There's no dedicated field for hashtags; they're just regex'd out of the markdown that makes up the post body and then processed to turn them into search links and style them. When you turn off the option to enable hashtags, you're actually turning off the processing step that runs the regex pattern to find them. In that case, they're still there as unstyled text in the post body.
Since there is logic to detect them, in theory, yes they can be hidden. But here's the "but" I mentioned:
There's no differentiation between inline hashtags such as I love #pancakes for breakfast and ones tacked onto the bottom of the post:
I love pancakes!
#Breakfast #Pancakes
So if I added an option to hide / not render the detected hashtags, inline ones would be hidden too.
e.g. I love #pancakes for breakfast would become I love for breakfast
Truth be told, the hashtag detection logic is some of the most annoying code in this project (among other challenges, markdown used in posts also uses the hash symbol for headings so you have to differentiate lest headings become partial hashtags). I really, really do not want to add on to that to try differentiate inline hashtags.
That said, it probably isn't feasible to completely hide hashtags unless I change my mind on refactoring the hashtag detection logic (not likely but you never know!)
I did see your post in Fediverse Memes (lol) so there is at least one thing I can offer: The version I have in dev has much more granular filtering capability. One such filter option is the ability to filter content by platform. This will allow you to hide posts/comments from users that are on specific software (e.g Mastodon).
