Is there an actual recommendation about insulation clearances around non-IC-rated recessed lighting fixtures, or should insulation just not touch them?
the minimum is a 3" clearance
Maintain 3 inches of clearance from insulation material. IRC 2003 N1102.11.2
I have seen many manufactures state in their instructions to keep at least 6" or 8" of clearance, depending on the style of can light.
About half of the ones I see have a sticker that says 3" clearance minimum. I always take a picture of it for the report. Make the point quite well.