What exactly makes Eagle "Horrible" ?
From what I have read so far all I can see is peoples inability to navigate and use it properly?
I have used Kicad, Diptrace, Altium, OrCad / Allegro, Pulsonix, Design Spark, Proteus, CadStar, Ultiboard and a few others when evaluating, I didn't end up making the final PCB run, bit I designed a board with 4 layers and about 500 pins, not all entirely what you might call "Licensed" evaluation copies, but some were and some didn't need licensing.
Anyway, I always used Eagle and another program called Ranger XL and was wondering at the time if there were any better CAD systems to use, I went by ease of use, how easy a footprint / component was to produce and how easy I could measure things on the layout.
I spent on / off about a year looking at these different packages, and I went to a design show where several were being showcased, I was already familiar with some packages as I use them at work.
My initial thoughts were that Proteus was a really good, nice to use package, but could be quite expensive, the likes of Altium and Orcad were quite good, had a lot of features that I didn't need and would never use, so in that respect made things a bit wasteful and seemingly more complicated to use.
Kicad is good for what it is, free.
Diptrace is very good, but apart from the interface, which is always going to look nicer as it was done in Delphi, didn't seem to be more intuitive or possess any immediate feature that would make me want to switch from Eagle.
From what I could gather they are both similarly matched in performance, I haven't found either to be particularly clunky in design, it really does come down to personal preference, Eagle arguably has the most parts in it's library and the fact you can download them direct from Farnell / Element 14 is a bonus, RS is doing something similar with Design Spark.
It really does boil down to the same question that people ask over and over again ( I asked myself at one point) which is the best PCB software to use? Answer: all of them, they all do things their own way and have their own pro's and con's, if you are doing high speed systems maybe Altium or Cadence is your best bet, I have seen DDR5 routed with Eagle no problem though, at the end of the day it is down to personal preference, they will all do what you want them to do, even Kicad these days is quite powerful.
So, my conclusion is that Eagle is not "shit" it is just not as easy to grasp as some of the other packages, you would be surprised (and maybe shocked) if you have seen some of the things that Eagle was used to design, it IS used in the industry for commercial and transport based systems and I am pretty sure I read that the Military use or used to use it as well for designs, I know of at least one company designing high speed cable testing facilities for the aerospace industry that use it as it was in one of their job descriptions!
Yes there are differences, there always will be, it's like comparing Windows to Linux, sure Windows isn't as open as Linux, but they both ultimately do the same job, and Windows didn't suffer from the "heartbleed" bug, unlinke Linux, which is a +1 for Windows.
Sorry for the long read, but it makes me laugh when people compare packages and call one crap and another brilliant because of some reason that boils down to misunderstanding or not RTFM.
For those wanting to chose a package, do what I did, download several, have a go in all of them, with the same design, it might seem pointless to begin with repeating work, especially if you have to make a footprint, and it will take some time, but will be worth it in the end, and after all, if you can't make a footprint then what's the point in trying to design a PCB? PCB Design is time consuming, so use a tool you are happy with rather that one someone said you should use because it can measure a track with one less click than another package.