Well, using 1984 as the anchor year (just on the cusp of indexed shifting), the inflation factor for the past 30 years (to 2014) is a factor of ~2.30.

So, an entry level road bike that is Sora equipped, has a triple crankset and reasonable but generic dual pivot brake calipers, can be had for ~$800-900 at a bike shop. This will have an aluminum frame and steel fork. Perormance will be at least as good or better than an entry level road bike from the earlier era. How about price? 800/2.3=$347, which would have been low-to-mid level in 1984, something better than the Super Mirage (~$200 range), but more around the Grand Touring.

Prices are up a bit, I guess.

Some things haven't changed that much...cranksets, for example. But bottom brackets have gotten better, maybe others would disagree, but I think that external bearing BBs are pretty nice. Shifting has improved, with integrated brake/shift lever technology. No question about that one (despite my preference for friction shifting on the bar end). Freehub and cassette combinations are better than the freewheel predecessors, right?

Lightweight racing saddles are better and more varied today, aren't they?

Maybe the costs are commensurate with the improvements. At least to the bike riding enthusiast.