So what is the problem? Only they know of course, but considering the amount of abuse women get on twitter, I'm gonna guess "reply" is understood.
If clicking comment both showed comments and had a space for you reply, more reflection *might* occur.
In any design there are at least two contexts to consider:
1. the software conventions
2. the user's world's conventions medium.com/@cwodtke/the-i…
This design violates both.
In this use, what does it mean? follow the person? Follow the conversation?
It simply means that more important elements get more visual weight, which can be accomplished by color/line weight/size etc....
We should also talk about gestalt principals esp proximity.
explorations in look/feel/language can lead to interesting features.
amzn.to/2OTmrpR
amzn.to/2FTW4M9
amzn.to/2UiA4Ve
and if you are broke at least read amzn.to/2UiA4Ve
USABILITY TESTING! It's a thing, people!
Twitter, forums have existed since the dawn of computers! Go look at 20 and figure out what to do!