Yes rgsgww, any non-metallic cables installed in accessible dwelling attics & installed away from the studs edge shall be physically protected & secured to running boards if within the measurements I mentioned earlier.
if is NOT a good idea to bury these junction boxes in the attic insulation since 1 it makes finding them later harder, but also, the conductors may NOT get the proper ventilation/cooling they may need if buried in insulation in a Hot SummerAttic envirement.
In an attic, stuff buried under insulation will be cooler than stuff in the open air. For example, last October 1st the outside temp at 4PM was about 95. The ambient air temp in my attic at the plate line above the insulation was about 95 or slightly higher. The air temp at the peak exhaust vent was 115. The temp under the insulation at the ceiling sheetrock was less than 80, about the same as the inside temp.