Thinking about it, I think that it comes down to the costumes intentions and how that kind of costumes are more appreciated nowadays.
Essentially, the point of the original Araña costume was practicality and commodity over the traditional superhero costumes. We all remember the scene where Anya makes fun of the more regular superhero costumes. So her reaction is "F-it, I'll make my own!". She choses to wear something that reflects her personality, is comfy and practical.
After that, they thought it would be a good idea to give her spandex. Jump to 2013/14 and we see that costumes that put commodity, practicality and reflect the character's personalities are all the rage (Batgirl, Ms. Marvel, Spider-Gwen and more recently Spider-Woman).
I can see where they were going with the upgraded SG costume, making her less vulnerable. As Wolverine points out, Spider-Man wears a costume just like her's and the only reason he's alive is for pure luck. The upgrade gave her more punch, made her less vulnerable and the hoodie helped covering her -long- pony tail. As Batman has taught us, is never a good idea to fight crime with your hair down. And just like the previous case, this is becoming a trend among superheroes (Captain Marvel and Batgirl).
Sadly, it seems that nobody liked the costume -personally, with some twitches here and there I think it could have worked- and editorial just decided to ignore it. In this case,they could have gone all the way and give her a new costume altogether rather than just an upgrade.
Something that Phantom Roxas pointed out and I hadn't realized: Silk and Gwen are basically replacements for Anya and May, respectively.
Silk replaces Anya as the only woc in the Spider-Family in 616; meanwhile, Gwen replaces May as the alternate universe Spider-Woman from realities where Peter is ooa. They're basically the candy to distract everyone from the changes (death?) that Anya and May will be suffering post-SV.