Interesting point.
It shouldn’t be considered “dangerous” any more than any other public sector role, but given the deaths of two serving MPs and threats made to others, then it clearly is.
Serving MPs are entitled to security, I think it might prove very costly to the public purse to provide security to all ex MPs, particularly in the light of the fact that many many MPs go onto make far more cash than they ever did as MPs.
If you consider this logically, people choose to enter public service, many no n-working Royals no longer have security paid for publicly and there’s far less of them than ex-MPs.
It’s a tough one to answer.