Stating the obvious too, no new level crossings are being built anyway. And slowly they are being removed.
Network rail has said it would get rid of everyone if it could.
The reopened Alloa branch (including the freight line to Longannet) is a good case study- the busy (and anticipated to be busy) level crossings were replaced by bridges where it was practical (in a couple of cases this has actually left relatively long road detours, turning previously through-roads into quiet side streets)- though some have had to be left as there's no sensible workaround. In many cases it simply isn't going to be practical- I can think of some local ones to me where the only solution I can envisage would involve putting the railway in a deep cutting- which would mean a lengthy line closure.