There was a lamp at my parents place that always gave a fairly strong "tingle" in operation. I dare say if it had an earth, the trip would have been going fairly constantly. My dad was adamant that all lamps lacked an earth connection. Maybe someone of the same school of thought?
I have wired the earth, I do have RCD protection and it’s not triggering.
I have removed and replaced all wiring, and lamp holder. Kept the old switch mind.