On most of my bikes I can watch the fork tips flexing while riding. On the Bates with the Diadrant fork (look it up- yes, steel) the fork tips move so much it startles other riders. The frame contributes nothing to ride comfort?
On any steel fork with significant rake try mounting a fender and then push down on the handlebar. Watch the tire come closer to the fender. If you have a stiff fork nothing will happen. With a flexible fork it doesn't take much load to get very visible suspension travel, with very flexible forks you might need to mount the fender higher.
Bikes are not all the same. Different ride characteristics can be engineered into steel, aluminum, titanium, or carbon. Ever ride a Vitus 979? Aluminum frames that were super flexible. Built in quantity for many years and won thousands of races. No aluminum frame remotely close to that in current production. If you buy production frames built in current era they are all massively stiff. The buying public asked for that. Or a vocal segment did. Now those who want something different have limited choices. Simplest is to ride wide tires and keep the pressure down. Or you can buy custom from a builder who listens when you ask him for something non-fashionable. Or you can ride old bikes. New bikes ride like brick walls. And windrows of commenters will tell you that is the only possibility. There is no alternative. Bollocks, there is always an alternative.
That Bates mentioned above is also the most precise steering bike I've owned. In spite of the fact that I am way heavier than would have been anticipated when the frame was built. A flexible fork is not a sloppy fork.