If i'm being perfectly honest, the new reply system is a bit... ugly.
The text is faded out and small, so it's difficult to read, and going to the message isn't a great option either, since jumping around the message logs can be a bit confusing and might make you lose track of the conversation (which seems like the exact opposite of what was intended)... Also, placing it above the person's username doesn't make much sense either, and just looks weird, same goes for changing the username area to include the person they replied to, it's confusing.
As far as i can tell the two major upsides of replies are the fact that they're not editable, and that they link to the source message, and as I don't like the idea of criticising something without giving a half decent suggestion as to how to fix it, so here's my idea: Merge the replies and quotes into one system. Any quote generated using the button (and not markdown) will looks a little bit different, maybe have the vertical bar colored blue, to show that it's unedited, of course it would go back to normal as soon as any change is made to the quote (this is a bit unrelated but if this is done, it would also be nice to disable link previews in quotes, since those are usually unnecessary, and i usually edit them out using markdown "<>"), as for message links, by this point we already have a fancy looking blue bar next to our quote, we might as well turn that bar (and surrounding empty space, to make it easier to click) into a button, that takes you directly to the message referenced!
Additionally, an option to change the style of quotes (maybe "Large VS Compact"?) could also help in case some people prefer the way replies look. (I personally don't, but opinions are subjective.)
Thanks for taking the time to read this, and i hope it will be taken into consideration.