Better in what way? Cameras have changed a lot in 5 years, with improved and higher resolutions sensors and new features. Hopefully those changes help photographers capture better images or images that were more difficult to capture in the past
There have been huge improvements in post-processing software like LR, PS, and Capture One. Most notable are the ease with which one can mask a subject and incrementally apply levels, NR, sharpness, etc... As a result, many pictures do have a more "polished" look. As for whether the work looks better or not, I'm not sure. Much of work posted now has a level of perfection that is unreal.
Great work past or present is great work... I think you are seeing the impact of ubiquitous post processing techniques that allow average work to appear good to great...
Technical quality has certainly improved over the years, and this trend will continue as the algorithms that power our cameras and software evolves.
The ability to make interesting and evocative images is still as difficult as ever. We are literally drowning is an ocean of pretty pictures that are perfect, and perfectly boring.
