I must admit I had not realised there was such a large variation in how carb heat is used. This discussion has certainly had me back checking to see what my POH has to say. There was nothing in there I could see about its use in landing to say whether it should be on or off.
My impression from what’s been said here is that different local practices around the use of carb heat have arisen in response to the typical needs of the aircraft and climate pilots are operating in.
Interestingly, it also seems to influence which engine parameters are being monitored. I have not so far seen carb temp monitors in aircraft where I fly but I have seen many exhaust gas temp monitors .
I think this is probably because the daytime temperatures that the average private pilot flies in around my part of the world are rarely below zero. The risk of applying carb heat and moving it into the icing range is consequently low. Whereas fuel prices are very high and the risk of wasting fuel or damaging an engine through improper leaning to reduce fuel burn is also high.
For myself carb heat comes off at 300ft on final. I fly an old Cessna 172 that has 40 degree flaps and only 145 hp max output from the engine. I need every ounce of power and minimum pilot workload if it is necessary to go around at the last minute with a full load and all the flaps out.