Because you long forgot how confusing it was, that you can't see if your keystrokes are accepted by the machine. This is a change for people, that are new to Linux/Unix

Worse than this issue, but kind of related, sometimes TTY1 (and maybe also the other TTYs) is being spammed by log info on boot, and if you have a TTY login it isn't obvious you can just log in anyway. Had a friend using Arch+i3 with TTY login, pretty new to GNU/Linux in general, so he kinda threw up his hands like "ah dang, can't log in, it's broken". I tried to tell him to just type his credentials anyway, but he didn't get what I was saying at first. Took a bit before we got him logged in and could address the other issues. I've had similar issues on my machines. I once had kernel log verbosity cranked up by accident, copied my config from another machine where I was chasing a GPU bug. Well, the same settings on the other machine were presenting way worse, constant never-ending line-spam, before and after login. Had to get into a graphical environment half-blind to see what I was doing and then turn down the verbosity. IMO there should be an easier way around that.

Good things always happen when you cater to the lowest common denominator.