As a boomer, I'd have to agree with most of your thesis. The primary piece I'd disagree with is the condo ownership. Instead of condo ownership, many may be staying in the lake house or buying into a senior housing facility. Another point I'd make is that boomers who are "into" real estate would be looking for an indication that the RE market has bottomed out before buying any new properties.
As for downsizing vs. upsizing, there are many tired seniors who are fed up with maintaining large houses (and lawns), but there are also plenty of status-conscious grandparents (perhaps a little younger and more vivacious than the average downsizer) who will be looking for a chance to buy the obnoxious $500K house for $350k or less if the opportunity arises (over-leveraged builder has to dump it, etc.).
Real-estate has tended to go up with inflation (except for the last ten years or so, when RE prices have significantly outstripped inflation). If demand for sawtimber and chip-n-saw drop precipitously with reduced (new) housing demand, there could be significant drops in the cost of materials for building a home, allowing price/SqFt to drop.
One last point, like you said, IRAs and 401Ks don't all have to be stock, and indeed that's true. My wife has set up a RothIRA dedicated to Real Estate investing, and the ROI in that account has been much better than the ROI in her regular IRA (stock investments) lately.
'peeker
PS> Thanks for the post last week pointing to the last time the Fed did the .50 cut in rates, the market was significantly lower six months later.