Actual state of affairs regarding landed gentry, ultimately (7)
I believe the answer is:
reality
'actual state of affairs' is the definition.
(how things really are)
'regarding landed gentry ultimately' is the wordplay.
'regarding' becomes 're' (re can mean regarding, concerning).
'landed' becomes 'alit' (alight can mean to land).
'ultimately' indicates one should take the final letters.
The last letter of 'gentry' is 'y'.
're'+'alit'+'y'='REALITY'
(Other definitions for reality that I've seen before include "The way things are, no illusions" , "The world as it is" , "Fact" , "All that is actual and not imaginary" , "as some TV programmes purport to show" .)