Assuming that foot access really is illegal and not just discouraged, if it definitely exists I'd tag it as something like "foot=no". If there isn't really a way from A to B but some people just run across the road, I probably wouldn't both bother tagging the crossing at all. [Here][1] is an example of that - clearly those paths used to connect, but there's no brak in the armco in the middle of the road and no easy way across. There's also no current signage suggesting the paths connect, either. [1]: https://www.openstreetmap.org/way/376900721#map=19/53.97062/-1.01997

Assuming that foot access really is illegal and not just discouraged, if it definitely exists I'd tag it as something like "foot=no". If there isn't really a way from A to B but some people just run across the road, I probably wouldn't both tagging the crossing at all. [Here][1] is an example of that - clearly those paths used to connect, but there's no brak in the armco in the middle of the road and no easy way across. There's also no current signage suggesting the paths connect, either. [1]: https://www.openstreetmap.org/way/376900721#map=19/53.97062/-1.01997