It will likely take 5 to 10 years, but eventually yes 4K (or even 8K) will be the norm...even among the casuals and the mass market. Not necessarily because casuals WANT 4K...as many are fine with 1080p or even 720p, but simply because:
a) existing TVs have a limited shelf life...things break and die, and it's sometimes cheaper and easier to just buy a new TV than repair the old one
b) by then, 50"-60" 4K TV will be affordable...people can buy quality brands (Panasonic, etc.) at $1,000 or less (way under $1K on Black Friday)
c) by then, 80%+ of the TVs available on the market at Amazon, Fry's, Best Buy etc. will be 4K TVs
d) by then, the vast majority of the television marketing will be targeted towards 4K TVs.
It also wouldn't hurt if there were some new multimedia that supported and really took advantage of 4K (or more) that further incentivized the masses to upgrade...and greater penetration of fiber connections (Google Fiber, etc.) would help on the streaming side.
32 channel audio does seem way overkill for most consumers for the foreseeable future, though.