The deviation I believe is explained mostly by the expectation that high rates will go down, and the very powerful behavioral economic concept of sticky downward prices.

The weakness of my first point is that the high long rates in the late 70s and early 80s reflected market expectations. The counter to this is that expectations of homebuyers and investors are not the same as major bond buyers, and also that the homebuyer only needs to hope rates dip once so they can refi. Further, lower liquidity in RE means marginal buyers expecting rates to dip have more power than in liquid bond markets.

Another thing keeping RE high when high rates make it unaffordable was the concern about runaway inflation. Those long bonds with 13% coupons were great in retrospect, but had a much worse downside than RE if inflation had moved into the 20%+ range.