A decade ago, nerds sometimes posited that in the future, connectivity will be so fast, RAM/storage space so large, and processors so powerful that the world might just switch to lossless formats. Here we are in 2014 still trying to trim a couple of percentage points off JPEG file sizes, and web designers still advise keeping images under 100k each or so.
Some of that is due to the rise of mobile computing. The computing power and data connectivity of mobile handsets are running about a decade behind desktop computers, so the least common denominator problem has remained somewhat static. And even as that market matures, rural areas and users will continue to lag for some time.
In addition, for any increase in computing power and data storage, we've often seen an equal increase in resolution and bit depth. A decade ago, 480p videos were the norm. Now we're now up to 1080p videos. Within a decade, it'll be 2160p videos. Same deal with digital cameras that have jumped from 5MP or less to 20MP or more today.
I'd argue that lossless formats like FLAC and ALAC were adopted early in the audio world because music files have generally remained fixed at 44.1kHz × 16bit × 2 channels. Movies have somewhat settled at 48.8kHz × 24bit × 6 channels (with 192kHz being the ceiling). They're also relatively small from the start. Lossless formats in the video world outside of the editing room or archival repository don't make sense. Same with raw image formats for cameras.
We've also seen an increase in the number of users, which in turn results in an increase in the amount of data. How many MySpace visitors were there in 2006? How about Facebook today? About ten times as many. And Facebook encourages more uploading than MySpace did. If people are satisfied with good enough, it just doesn't make economic sense to go lossless.