I also wonder if the retirement as we know it now (at least in the U.S.) will become a historical anomaly...
I suspect you are right. Change is the only constant. Retirement was already different for the two prior generations in my own lineage.
Both my grandfathers passed on at about age 50. One grandmother made it to about 70, but from my earliest recollection she was always frail, and was mostly bedridden the last ~5 years of her life. A lifelong smoker, it was an accomplishment to make it as far as she did. Neither pensions nor savings did any of them much good.
OTOH, my parents are still rockin' it in their 80s, enjoying the fruits of both DB and DC vehicles. My father rode the peak of the pension era, enjoying a COLAd federal check for the past 25 years, while my mom collects SS and also gets RMDs from an IRA still worth more now than when she retired.
So, what will retirement look like when I enter it? Considering my family history, whether I end up rich or poor should be of only minor concern. Much more important will be whether I replicate the robust health of my immediate predecessors.
To the OP: It's too early for me to tell what my net worth will be when I RE, since it's still a ways off. Somewhere between 1M and 2M, so probably doesn't qualify for your survey.