isa, your questions raise interesting aspects, which may have no simple answer.
First, consider if there are different standards, requirements, or terminology between 'old' aircraft and those which are used today.
Thus RCR (Runway Condition Report ?), is now described by category where the contributing factors in each reduce the braking effectiveness; e.g. 6 dry, 5 wet, … Are we discussing the same issue ?
The assumption might be that wheel side-force is related to RCR, but the science is wide ranging - runway texture, drainage, tyre type or tread, … Also, that the categorisations and certification are based on more recent science - not just the old wet vs dry runway.
Then there is the possibility of a complex mix of wheel/ runway forces and the aerodynamic contributions; rudder / reverse have greater effect at higher speeds.
Additionally, the methods of determining an acceptable 'demonstrated' value have changed / changing, particularly in considering crosswind gusts and flight test demonstrations; these and published demonstrated values vary between manufacturers and regulators, civil military - even if there appears harmony with the use of RCR.
Overall there does-not appear to be an instant answer, but at least interesting questions to keep on considering.